<PAGE>

                                                                     EXHIBIT 4.1

                                  FORM OF NOTE

         THIS NOTE HAS BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR
         FOR SALE IN CONNECTION WITH, THE DISTRIBUTION THEREOF. THIS NOTE HAS
         NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
         ANY STATE SECURITIES LAWS, AND MAY NOT BE PLEDGED, SOLD, OFFERED FOR
         SALE, TRANSFERRED, OR OTHERWISE DISPOSED OF IN THE ABSENCE OF
         REGISTRATION UNDER OR EXEMPTION FROM SUCH ACT AND ALL APPLICABLE STATE
         SECURITIES LAWS.

                               CRITICAL PATH, INC.

                    CONVERTIBLE SUBORDINATED PROMISSORY NOTE

$___________________                                   San Francisco, California
                                                       November ____, 2003

                  Critical Path, Inc., a California corporation (the "Company"),
the principal office of which is located in San Francisco, California, for value
received hereby promises to pay to the order of _____________________________,
or its registered assigns ("Holder"), the sum of _______________________________
dollars ($_________), or such lesser amount as shall then equal the outstanding
principal amount hereof on the terms and conditions set forth hereinafter. The
outstanding principal amount hereof and all accrued and unpaid interest hereon,
as set forth below, shall be due and payable on the earlier to occur of (i)
November ____, 2007, (ii) when declared due and payable by Holder upon the
occurrence of an Event of Default (as defined below), (iii) consummation of a
Qualified Asset Sale, (iv) a Change of Control, or (v) any sale of capital stock
or Stock Equivalents by the Company, any cash capital contribution from any
third person or any other debt or equity financing consummated by the Company
after the date of issuance of this Note which, in the case of (v), individually
or in the aggregate raises proceeds of at least forty million dollars
($40,000,000) in cash or cash equivalents (the earliest of the events set forth
in items (i)-(v) immediately above, the "Maturity Date"); provided, however,
that in the event that the Maturity Date is on or before November ____, 2004,
the Company shall also make an additional payment to Holder equal to the amount
of interest which would have otherwise accrued on the outstanding principal
amount of the Note on the Maturity Date between the Maturity Date and November
____, 2004.

                  The following is a statement of the rights of the Holder of
this Note and the conditions to which this Note is subject, and to which the
Holder hereof, by the acceptance of this Note, agrees:

                  1.       Definitions. Except as otherwise defined herein, each
capitalized

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                                                                               2

term used herein shall have the meaning assigned to it in the Purchase
Agreement, as in effect on the date hereof, and without regard to any subsequent
termination of the Purchase Agreement. All other references to the Purchase
Agreement in this Note refer to the Purchase Agreement as in effect on the date
hereof, and without regard to any subsequent termination of the Purchase
Agreement. As used in this Note, the following terms, unless the context
otherwise requires, have the following meanings:

                           1.1      "Affiliate" means any Person who is an
"affiliate" as defined in Rule 12b-2 of the General Rules and Regulations of the
Securities Exchange Act of 1934, as amended.

                           1.2      "Capitalized Lease Obligations" means, with
respect to any Person, all rental obligations of such Person which, under GAAP,
are or will be required to be capitalized on the books of such Person, in each
case taken at the amount thereof accounted for as indebtedness in accordance
with such principles.

                           1.3      "Change of Control" shall mean (i) any
merger, consolidation or other business combination transaction (or series of
related transactions) in which the stockholders owning a majority of the voting
securities of the Company prior to such transaction do not own a majority of the
voting securities of the surviving entity, (ii) any tender offer, exchange offer
or other transaction whereby any Person or "group" (as defined in Rule 13d-3 of
the General Rules and Regulations of the Securities Exchange Act of 1934, as
amended) (other than General Atlantic Partners 74, L.P., GAP Coinvestment
Partners II, L.P., GapStar, LLC, GAP-W, LLC, GAPCO GmbH & Co. KG, Campina
Enterprises Limited, Cenwell Limited, Great Affluent Limited, Dragonfield
Limited and Lion Cosmos Limited and the Affiliates of the foregoing, provided
that Affiliates shall be deemed not to include any portfolio companies of any of
the foregoing) obtains a majority of the outstanding shares of capital stock
entitled to vote in the election of directors, (iii) any proxy contest in which
a majority of the Board of Directors of the Company (or persons appointed by
such Board of Directors) prior to such contest do not constitute a majority of
the Company's Board of Directors after such contest or (iv) any other
transaction described in any stockholder rights agreement or "poison pill," if
any, to which the Company is party, which may permit the holders of any rights
or similar certificates to exercise the rights evidenced thereby.

                           1.4      "Company" shall have the meaning set forth
in the recitals hereto, and includes any corporation that shall succeed to or
assume the obligations of the Company under this Note.

                           1.5      "Conversion Date" shall mean the Subsequent
Closing Date.

                           1.6      "Designated Preferred Stock" shall mean the
Series D Preferred Stock, par value $0.001, of the Company and the Series E
Preferred Stock.

                           1.7      "Domestic Subsidiary" shall have the meaning
set forth in Section 5.10 hereof.

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                                                                               3

                           1.8      "Event of Default" shall have the meaning
set forth in Section 6 hereof.

                           1.9      "Guaranteed Interest" shall mean the total
amount of interest that would accrue on this Note, at the Interest Rate
specified in Section 2, from the date of this Note until the one year
anniversary of the date of this Note.

                           1.10     "Guarantor" shall have the meaning set forth
in the Security Agreement.

                           1.11     "Holder" shall mean the registered holder of
this Note from time to time, and in the plural, shall mean all registered
holders of Notes from time to time issued by the Company pursuant to the
Purchase Agreement.

                           1.12     "Interest Amount" shall have the meaning set
forth in Section 3.1 hereof.

                           1.13     "Investment" means (i) the acquisition
(whether for cash, property, services, assumption of Indebtedness, securities or
otherwise) of assets (other than equipment, inventory, supplies or other assets
acquired in the ordinary course of business of the Company), capital stock,
bonds, notes, debentures, partnership, joint venture or other ownership
interests or other securities of any Person, (ii) any deposit with, or advance,
loan or other extension of credit to, or on behalf of, any Person (other than
deposits made in connection with the purchase of equipment, inventory, services,
leases, supplies or other assets in the ordinary course of business of the
Company), (iii) any other capital contribution to or investment in such Person,
including, without limitation, any guaranty obligation incurred for the benefit
of such Person. For the sake of clarity, Investments shall include any transfer
of property or assets by the Company to any of its Subsidiaries or by any
Subsidiary of the Company to any other Subsidiary.

                           1.14     "Loan Documents" shall have the meaning set
forth in the Security Agreement.

                           1.15     "Note" shall mean this note, and in the
plural, shall mean all notes issued to the Lenders pursuant to the terms of the
Purchase Agreement, including this Note, and all amendments, modifications and
extensions thereto.

                           1.16     "Permitted Investments" means (i)
Investments in cash or cash equivalents, (ii) accounts receivable created,
acquired or made in the ordinary course of business and payable or dischargeable
in accordance with customary trade terms; (iii) Investments existing on the
closing date, and listed on Schedule ___ to the Purchase Agreement, (iv)
guaranty obligations permitted by Section 5.3 of this Agreement, (v) loans to
employees, directors or officers of the Company in connection with the award of
convertible bonds or capital stock under a stock incentive plan, stock option
plan or other equity-based compensation plan or arrangement, (vi) other advances
or loans to employees, directors, officers or agents of the Company in the
ordinary course of business not to exceed $500,000 in the aggregate at any time
outstanding; (vii) loans, advances and investments in foreign Subsidiaries (that
are not incorporated or otherwise

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                                                                               4

organized under the laws of the United States of America or any state thereof)
in an amount not to exceed $1,000,000 in the aggregate at any time outstanding;
(viii) any acquisition for which the prior written consent of the Holders of a
majority of the outstanding principal amount of all of the Notes issued by the
Company pursuant to the Purchase Agreement has been obtained, (ix) other loans,
advances and investments of a nature not contemplated by the foregoing sections
in an amount not to exceed $500,000 in the aggregate at any time outstanding or
(x) Investments by the Company in the Guarantor.

                           1.17     "Permitted Liens" shall have the meaning set
forth in Section 5.4.

                           1.18     "Person" means any individual, firm,
corporation, partnership, trust, joint venture, joint stock company, limited
liability company, Governmental Authority or other entity of any kind, and shall
include any successor (by merger or otherwise) of such entity.

                           1.19     "Price Per Share" shall have the meaning
attributed to such term in the Series E Certificate of Determination, as filed
with the Secretary of State of the State of California.

                           1.20     "Purchase Agreement" means that certain
Convertible Note Purchase and Exchange Agreement, dated November 18, 2003, among
the Company, the Holder and the other parties thereto from time to time, and all
amendments, modifications and extensions thereto.

                           1.21     "Qualified Asset Sale" means the sale,
transfer or other disposition of any of the assets of the Company or any of its
Subsidiaries, other than (a) sales of assets in the ordinary course of business,
(b) sales of assets where the proceeds are used to repay Indebtedness owing to
SVB, (c) the sale, transfer or other disposition of assets of the Company where
the proceeds are applied to the purchase price or traded in for credit against
the purchase price of other assets, provided that any such purchase is made, or
credit issued, within 90 days of the sale, transfer or other disposition, and
(d) one or more sales of the Company's assets (other than sales otherwise
included in clauses (a), (b), and (c) immediately above) which collectively
yield up to an aggregate of one million dollars ($1,000,000) in gross proceeds
to the Company while this Note is outstanding.

                           1.22     "Restricted Payment" means (a) any dividend
or other distribution (whether in cash, securities or other property) with
respect to any shares of any class of capital stock of the Company or any of its
Subsidiaries or (b) any payment (whether in cash, securities or other property),
including any sinking fund or similar deposit, on account of the purchase,
redemption, retirement, acquisition, cancellation or termination of any shares
of any class of capital stock of the Company or any Subsidiary or any option,
warrant or other right to acquire any such shares of capital stock of the
Company or any Subsidiary.

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                                                                               5

                           1.23     "Security Agreement" means that certain
Guaranty and Security Agreement, of even date herewith between the Company,
Compass Holding Corp., the Lenders and the other parties thereto from time to
time, and all amendments, modifications and extensions thereto.

                           1.24     "Series E Conversion Price" shall have the
meaning set forth in the Series E Certificate of Determination.

                           1.25     "Series E Preferred Stock" means the Series
E Preferred Stock, par value $0.001, of the Company.

                           1.26     "Subordination Agreement" shall have the
meaning set forth in Section 5.3.

                           1.27     "SVB" means Silicon Valley Bank, a
California chartered bank, or any Affiliates thereof.

                           1.28     "UCC" shall have the meaning set forth in
Section 5.4.

                  2.       Interest. Simple interest shall accrue at the rate of
ten percent (10%) per annum (or such lesser amount as shall equal the highest
rate of interest allowable under applicable law) (the "Interest Rate"), on the
outstanding principal of this Note from the date of this Note until the Maturity
Date or the date this Note is otherwise repaid. The Company shall not be
obligated to make any payments of interest which shall have accrued under this
Note prior to the Maturity Date. Interest shall be calculated on the basis of a
360-day year for the actual number of days elapsed. In the event that the
principal amount of this Note, any interest, or any amount payable hereunder is
not paid in full when such amount becomes due and payable, or upon the
occurrence of an Event of Default, interest shall accrue at the lesser of (a)
the initial Interest Rate plus five percent (5%) per annum or (b) the highest
rate of interest allowable under applicable law, on the balance of all amounts
outstanding until such overdue amounts are paid or the Event of Default is
cured, and such interest shall be payable on demand.

                  3.       Conversion.

                           3.1      Conversion. On the Conversion Date, the
principal amount of this Note plus the greater of (i) the accrued and unpaid
interest thereon and (ii) the Guaranteed Interest (the greater of clause (i) and
(ii), the "Interest Amount"), shall be automatically converted into the number
of fully paid and nonassessable shares of Series E Preferred Stock equal to the
quotient obtained by dividing (a) the entire principal amount of this Note plus
the Interest Amount by (b) the Price Per Share.

                           3.2      Notice of Conversion. Upon conversion of
this Note as provided in Section 3.1, Holder shall surrender this Note to the
Company and shall state the name or names in which the certificate or
certificates for such shares of Series E Preferred Stock are to be issued. The
Person or Persons entitled to receive the shares of Series E Preferred Stock
issuable upon such conversion shall be treated for all purposes

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                                                                               6

as the record holder or holders of such shares of Series E Preferred Stock as of
the Conversion Date.

                           3.3      Delivery of Stock Certificates. On the
Conversion Date, the Company at its expense will issue and deliver to Holder of
this Note a certificate or certificates (bearing such legends as are required by
applicable state and federal securities laws in the opinion of counsel to the
Company) for the number of full shares of Series E Preferred Stock issuable upon
such conversion.

                           3.4      Mechanics and Effect of Conversion. No
fractional shares of Series E Preferred Stock shall be issued upon conversion of
this Note. In lieu of the Company issuing any fractional shares to Holder upon
the conversion of this Note, the Company shall pay to Holder the amount of
outstanding principal and interest that is not so converted. Upon conversion of
all amounts due under this Note, the Company shall be released from all of its
obligations under this Note.

                  4.       Adjustments. The number of shares of Series E
Preferred Stock convertible hereunder are subject to adjustment from time to
time as follows:

                           4.1      Merger, Sale of Assets, Etc. Subject to
Section 4.2, if at any time while this Note remains outstanding and unexpired
there shall be (a) a reorganization (other than a combination, reclassification,
exchange or subdivision of shares otherwise provided for herein), (b) a merger
or consolidation of the Company with or into another corporation in which the
Company is not the surviving entity, or a merger in which the Company is the
surviving entity but the shares of the Company's capital stock outstanding
immediately prior to the merger are converted by virtue of the merger into other
property, whether in the form of securities, cash or otherwise or (c) a sale or
transfer of the Company's stock, properties or assets as, or substantially as,
an entirety to any other Person, then, as a part of such reorganization, merger,
consolidation, sale or transfer, lawful provision shall be made so that Holder
shall thereafter be entitled to receive by converting this Note the number of
shares of stock or other securities or property of the successor corporation
resulting from such reorganization, merger, consolidation, sale or transfer that
a holder of the shares deliverable upon conversion of this Note would have been
entitled to receive in such reorganization, consolidation, merger, sale or
transfer if this Note had been converted immediately before such reorganization,
merger, consolidation, sale or transfer (notwithstanding that the Stockholder
Approval may not yet have been obtained), all subject to further adjustment as
provided in this Section 4. The foregoing provisions of this Section 4.1 shall
similarly apply to successive reorganizations, consolidations, mergers, sales
and transfers and to the stock or securities of any other corporation. If the
per share consideration payable to Holder hereof for shares in connection with
any such transaction is in a form other than cash or marketable securities, then
the value of such consideration shall be determined in good faith by the
Company's Board of Directors based on the amount the Holder would have otherwise
been entitled to receive had the transaction or transactions not occurred. In
all events, appropriate adjustment (as determined in good faith by the Company's
Board of Directors) shall be made in the application of the provisions of this
Note with respect to the rights and interests of Holder after the transaction,
to the end that the

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                                                                               7

provisions of this Note shall be applicable after that event, as near as
reasonably may be, in relation to any shares or other property deliverable after
that event upon conversion of this Note. The Company shall be obligated to
retain and set aside, or otherwise make fair provision for exercise of the right
of the Holder to receive, the shares of stock and/or other securities, cash or
other property provided for in this Section 4.1.

                           4.2      Election of Holder upon Merger or Sale of
Assets. Notwithstanding anything to the contrary contained herein, if an event
shall occur as provided in Section 4.1 hereof that would otherwise result in the
occurrence of the Maturity Date pursuant to clause (iii) or (iv) of the first
paragraph of this Note, then the Holder may, in its sole discretion, by written
notice to the Company elect to convert the principal amount of this Note plus
the Interest Amount into the number of shares of stock or other securities or
property described in Section 4.1, in lieu of receiving payment in full of all
amounts outstanding under this Note. The number of shares of stock or other
securities or property to be issued upon such conversion shall be determined in
accordance with Section 4.1 hereof, taking into account the occurrence of such
event.

                           4.3      Reclassification, Etc. If the Company shall,
at any time while this Note, or any portion thereof, remains outstanding and
unexpired, by reclassification of securities or otherwise, change any of the
securities as to which conversion rights under this Note exist into the same or
a different number of securities of any other class or classes, this Note shall
thereafter represent the right to acquire such number and kind of securities as
would have been issuable with respect to the securities that were subject to the
conversion rights under this Note immediately prior to such reclassification or
other change, and the Price Per Share shall be appropriately adjusted, all
subject to further adjustment as provided in this Section 4.

                           4.4      Split, Subdivision or Combination of Shares.
If the Company at any time while this Note, or any portion thereof, remains
outstanding and unexpired shall split, subdivide or combine the shares of Series
E Preferred Stock into a different number of securities of the same class, the
Price Per Share shall be proportionately adjusted.

                           4.5      Series E Adjustments. The initial Series E
Conversion Price of the shares of Series E Preferred Stock issued upon
conversion of this Note pursuant to Section 3.1 shall equal the Series E
Conversion Price in effect on the Conversion Date, subject to the adjustment of
such Series E Conversion Price from time to time thereafter as provided in the
Series E Certificate of Determination.

                           4.6      Certificate as to Adjustments. Upon the
occurrence of each adjustment or readjustment pursuant to this Section 4, the
Company at its expense shall promptly compute such adjustment or readjustment in
accordance with the terms hereof and furnish to Holder a certificate setting
forth such adjustment or readjustment and showing in detail the facts upon which
such adjustment or readjustment is based.

                           4.7      No Impairment. The Company will not, by any
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms to be

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                                                                               8

observed or performed hereunder by the Company, but will at all times in good
faith assist in the carrying out of all the provisions of this Section 4 and in
the taking of all such action as may be necessary or appropriate in order to
protect the rights of Holder against impairment.

                  5.       Covenants. The Company covenants and agrees that
until the earlier of (i) the date on which all Obligations (as defined in the
Security Agreement) have been paid in full or (ii) the Conversion Date:

                           5.1      Financial Statements and Other Information.
The Company shall deliver to the Holder of this Note the financial statements
and other information required to be delivered under Section 8.1 of the Purchase
Agreement.

                           5.2      Financial Covenants. The Company shall at
all times comply with the financial and other covenants set forth in Schedule
8.5 to the Purchase Agreement as if such covenants were set forth herein.

                           5.3      Indebtedness. The Company shall not, and
shall not permit any Subsidiary to, issue, incur, assume, create or have
outstanding any Indebtedness, provided, however, that the foregoing shall not
restrict nor operate to prevent:

                                    (a)      Indebtedness in favor of the
Holders under the Loan Documents;

                                    (b)      Indebtedness existing on the date
hereof, and as set forth on Schedule 3.22 to the Purchase Agreement;

                                    (c)      Indebtedness for accounts payable
incurred in the ordinary course of business by the Company;

                                    (d)      Indebtedness incurred solely for
the purpose of financing the acquisition of any equipment, machinery, software,
improvements or any other similar property, or extensions, renewals or
replacements of any of the foregoing for the same or a lesser amount; provided,
that the aggregate outstanding principal amount of all Indebtedness permitted
pursuant to this clause (d) outstanding for more than sixty (60) days after the
incurrence of such Indebtedness shall not at any time exceed $500,000;

                                    (e)      Indebtedness of the Company
evidenced by Capitalized Lease Obligations, provided, that in no event shall the
aggregate principal amount of Capitalized Lease Obligations permitted by this
clause (e) exceed $500,000 at any time outstanding; and

                                    (f)      Any extension renewal, refinancing,
refunding, or replacement (each, a "refinancing") of Indebtedness permitted by
clauses (b) and (e) above, on such terms and conditions as are, on the whole,
not materially more onerous to the Company than the terms and conditions of such
original Indebtedness on the date of

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                                                                               9

such refinancing (including that the principal amount of such refinancing
Indebtedness does not exceed the principal amount of, plus the amount of accrued
and unpaid interest on, the Indebtedness so refinanced (plus the amount of
reasonable premium and fees and expenses incurred in connection therewith)),
provided that, in the case of a refinancing of Indebtedness owed by the Company
or any Subsidiary to SVB, this clause (f) shall only apply to the extent
consistent with the Subordination Agreement, dated as of the date hereof, by and
among SVB, the Holders and the Company (the "Subordination Agreement").

                           5.4      Liens. The Company shall not, and shall not
permit any of its Subsidiaries to, create, incur, assume or suffer to exist any
Lien upon or with respect to any property or assets (real or personal, tangible
or intangible) of the Company or any of its Subsidiaries, whether now owned or
hereafter acquired, or sell any such property or assets subject to an
understanding or agreement, contingent or otherwise, to repurchase such property
or assets (including sales of accounts receivable), or assign any right to
receive income or permit the filing of any financing statement under the Uniform
Commercial Code, as from time to time in effect in the relevant jurisdiction
(the "UCC"), or any other similar notice of Lien under any similar recording or
notice statute; provided, that the provisions of this Section 5.4 shall not
prevent the creation, incurrence, assumption or existence of the following:

                                    (a) Liens arising in the ordinary course of
business by statute in connection with worker's compensation, unemployment
insurance, old age benefits, social security obligations, statutory obligations
or other similar charges (other then Liens arising under ERISA), good faith cash
deposits in connection with tenders, contracts or leases to which the Company or
any Subsidiary is a party or other cash deposits required to be made in the
ordinary course of business, provided, that such Liens do not have a material
adverse effect on the ability of the Company to repay amounts due under the
Notes;

                                    (b) inchoate Liens for taxes, assessments or
governmental charges or levies not yet due or Liens for taxes, assessments or
governmental charges or levies being contested in good faith and by appropriate
proceedings for which adequate reserves have been established in accordance with
GAAP;

                                    (c) Liens in respect of property or assets
of the Company or its Subsidiaries imposed by law, which were incurred in the
ordinary course of business and do not secure Indebtedness for borrowed money,
such as carriers', warehousemen's, materialmen's and mechanics' liens and other
similar Liens arising in the ordinary course of business, and (i) which do not
in the aggregate materially detract from the value of the Company's and its
Subsidiaries' property or assets taken as a whole or result in a material
adverse effect on the Condition of the Company or (ii) which are being contested
in good faith by appropriate proceedings, which proceedings have the effect of
preventing the forfeiture or sale of the property or assets subject to any such
Lien;

                                    (d) the pledge of assets for the purpose of
securing an appeal, stay or discharge in the course of any legal proceeding,
provided that the

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                                                                              10

aggregate amount of liabilities of the Company and its Subsidiaries secured by a
pledge of assets permitted under this subsection, including interest and
penalties thereon, if any, shall not be in excess of $500,000 at any one time
outstanding;

                                    (e) any interest or title of a lesser under
any operating lease;

                                    (f) easements, rights-of-way, restrictions
and other similar encumbrances against real property incurred in the ordinary
course of business;

                                    (g) the Liens existing on the date hereof
identified on Schedule 3.22 to the Purchase Agreement;

                                    (h) Liens on cash deposited with account
debtors to secure performance by the Company or any Subsidiary in the ordinary
course of business subject to customary and reasonable terms;

                                    (i) Liens upon assets of the Company or its
Subsidiaries subject to Capitalized Lease Obligations, provided, that (A) such
Liens only serve to secure the payment of Indebtedness permitted by Section
5.3(e) arising under such Capitalized Lease Obligation and (B) the Lien
encumbering the asset giving rise to the Capitalized Lease Obligation does not
encumber any other asset of the Company or its Subsidiaries;

                                    (j) Liens placed upon equipment, machinery,
software, improvements or any other similar property, used in the ordinary
course of business of the Company or any of its Subsidiaries at the time of the
acquisition thereof by the Company or any of its Subsidiaries or within ninety
(90) days thereafter to secure Indebtedness permitted by Section 5.3(d) above;
provided, that the Liens encumbering the equipment, machinery software,
improvements or any other similar property so acquired do not encumber any other
asset of the Company or its Subsidiaries;

                                    (k) set-off rights of depository
institutions; and

                                    (l) Liens created by the Security Agreement
(collectively with clauses (a) through (k) hereof, the "Permitted Liens").

                           5.5      Fundamental Changes. The Company will not,
and will not permit any Subsidiary to, merge into or consolidate with any other
Person, or permit any other Person to merge into or consolidate with it, or
sell, transfer, lease or otherwise dispose of (in one transaction or a series of
transactions) all or substantially all of its assets, or all or substantially
all of the stock of any of its Subsidiaries (in each case, whether now owned or
hereafter acquired), or liquidate or dissolve, except that, if at the time and
immediately after giving effect thereto no Event of Default shall have occurred
and be continuing (i) the Company or any of its Subsidiaries may, with the prior
written consent of the Holders, merge with or into any other Person; (ii) any
wholly-owned Subsidiary of the Company (other than the Guarantor) may merge with
or into the Company or any other wholly-owned Subsidiary of the Company; (iii)
any Subsidiary

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                                                                              11

(other than the Guarantor, and except as otherwise prohibited by this Note) may
sell, transfer, lease or otherwise dispose of its assets to the Company or to
another wholly-owned Subsidiary of the Company; and (iv) any Subsidiary may
liquidate or dissolve if the board of directors of the Company determine in good
faith that such liquidation or dissolution is in its best interests and is not
disadvantageous to the Holders.

                           5.6      Restricted Payments. The Company will not,
and the Company will not permit any Subsidiary to, declare or make, or agree to
pay or make, directly or indirectly, any Restricted Payment, except that (i) any
Subsidiary may make a Restricted Payment to the Company or any of its
wholly-owned Subsidiaries, and (ii) the Company or any of its Subsidiaries may
make any Restricted Payment required by the terms of the Purchase Agreement and
the other documents executed in connection therewith.

                           5.7      Transactions with Affiliates. The Company
will not, and the Company will not permit any Subsidiary to, sell, lease or
otherwise transfer any property or assets to, or purchase lease or otherwise
acquire any property or assets from, or otherwise engage in any other
transactions with, any of its Affiliates, except (a) transactions that are at
prices and on terms and conditions not less favorable to the Company or such
Subsidiary than could be obtained on an arm's length basis from unrelated third
parties, (b) transactions exclusively between the Company and the Guarantor and
(c) transactions under the agreements listed on Schedule 3.17 to the Purchase
Agreement.

                           5.8      Investments. The Company will not, and the
Company will not permit any Domestic Subsidiary (as hereinafter defined) to,
make an Investment in any Person, except for Permitted Investments.

                           5.9      Nature of Business. The Company will not,
and the Company will not permit any Subsidiary to, engage in any business other
than that conducted on the date hereof and any businesses reasonably related
thereto.

                           5.10     Property of Existing Domestic Subsidiaries.
The Company will not permit, or suffer to allow, any Subsidiary that is
incorporated or otherwise organized under the laws of the United States of
America or any state thereof (a "Domestic Subsidiary"), excluding the Guarantor,
to (i) own, hold, lease, license, purchase or otherwise acquire any personal or
real property (excluding any material intellectual property) in excess of
$50,000 for all property held by such Subsidiary, or $250,000 in the aggregate
for all property held by all Domestic Subsidiaries (ii) maintain any deposit
account in its name, (iii) own or otherwise hold any rights to any material
intellectual property or (iv) otherwise conduct any business or maintain
operations.

                           5.11     Formation of Subsidiaries. The Company will
not, and will not cause or permit any of its Subsidiaries to, form, acquire or
permit the existence of any new domestic Subsidiary, without causing such
domestic Subsidiary to execute and deliver to the Holders a secured guaranty of
the Notes and related security document, in form and substance satisfactory to
the Holders.

<PAGE>

                                                                              12

                           5.12     Books and Records. The Company shall keep
proper books of record and account, in which full and correct entries shall be
made of all financial transactions and the assets and business of the Company
and its Subsidiaries in accordance with GAAP consistently applied.

                           5.13     Inspection. The Company shall, and shall
cause each of its Subsidiaries to, permit representatives of the Holders to
visit and inspect any of its properties, to examine its corporate, financial and
operating records and make copies thereof or abstracts therefrom, and to discuss
its affairs, finances and accounts with their respective directors, officers and
independent public accountants, all at such reasonable times during normal
business hours and as often as may be reasonably requested upon notice to the
Company.

                           5.14     Maintenance of Business. The Company shall,
and shall cause each Subsidiary to, preserve and maintain its existence. The
Company shall, and shall cause each Subsidiary to, preserve and keep in force
and effect all licenses, permits, franchises, approvals, patents, trademarks,
trade names, trade styles, copyrights, and other property rights necessary to
the proper conduct of its business, except where the failure to do so could not
reasonably be expected to have a material adverse effect on the Condition of the
Company or on the prospects of repayment of the Notes.

                           5.15     Maintenance of Properties. The Company
shall, and shall cause each Subsidiary to, maintain, preserve and keep its
property and equipment in good repair, working order and condition (ordinary
wear and tear excepted) and shall from time to time make all needful and proper
repairs, renewals, replacements, additions and betterments thereto so that at
all times the efficiency thereof shall by fully preserved and maintained, except
in each case to the extent that, in the reasonable business judgment of such
Person, any such property or equipment is no longer necessary for the proper
conduct of the business of such Person.

                  6.       The occurrence of any one or more of the following
events shall constitute an "Event of Default":

                           6.1      Failure To Pay. (i) The failure of the
Company to pay any principal due under any of the Notes when due and payable
(whether by acceleration, declaration, extension or otherwise), or (ii) the
failure of the Company to pay any other amounts due under any of the Notes when
due and payable if such failure is not cured within five (5) days of Company's
receipt of notice thereof from any of the Holders.

                           6.2      Financial Covenants. The failure of Company
or any of its Subsidiaries to perform, observe or comply with any of the
Financial Covenants set forth on Schedule 8.5 to the Purchase Agreement, and
incorporated by reference in this Note in Section 5.2.

                           6.3      Other Covenants and Agreements. The failure
of Company or any of its Subsidiaries to perform, observe or comply with any of
the covenants of this Note, the Security Agreement or any of the other Loan
Documents (other than the

<PAGE>

                                                                              13

Financial Covenants set forth on Schedule 8.5 to the Purchase Agreement, and
incorporated by reference in this Note in Section 5.2), if such failure is not
cured within sixty (60) days.

                           6.4      Representations and Warranties. If any
representation or warranty made by the Company or any of its Subsidiaries in the
Loan Documents is not true and correct in all material respects on the Initial
Closing Date.

                           6.5      Default on Other Obligations. The occurrence
of any condition or default under any other indebtedness for borrowed money of
the Company or any of its Subsidiaries with a principal amount of at least five
hundred thousand dollars ($500,000) that results in the acceleration of such
indebtedness which is not cured within sixty (60) days.

                           6.6      Involuntary Bankruptcy. There shall be filed
against the Company or any of its Subsidiaries an involuntary petition or other
pleading seeking the entry of a decree or order for relief under the United
States Bankruptcy Code or any similar federal or state insolvency or similar
laws ordering: (a) the liquidation of the Company or any of its Subsidiaries or
(b) a reorganization of the Company or any of its Subsidiaries or the business
and affairs of the Company or any of its Subsidiaries or (c) the appointment of
a receiver, liquidator, assignee, custodian, trustee or similar official for the
Company or any of its Subsidiaries of the property of the Company or any of its
Subsidiaries.

                           6.7      Voluntary Bankruptcy. The commencement by
the Company or any of its Subsidiaries of a voluntary case under the federal
bankruptcy laws or any federal or state insolvency or similar laws or the
consent by the Company or any of its Subsidiaries to the appointment of or
taking possession by a receiver, liquidator, assignee, trustee, custodian or
similar official for the Company or any of its Subsidiaries of any of the
property of the Company or any of its Subsidiaries or the making by the Company
or any of its Subsidiaries of an assignment for the benefit of creditors, or the
failure by Company or any of its Subsidiaries generally to pay its debts as the
debts become due.

                           6.8      Judgments, Awards. Any judgment or order for
the payment of money is rendered against the Company or any of its Subsidiaries
in an amount in excess of five hundred thousand dollars ($500,000) individually
or in the aggregate and either (i) enforcement proceedings are commenced by any
creditor upon such judgment or order and not stayed, or (ii) there is any period
of sixty (60) consecutive days during which such judgment has not been paid in
full or a stay of enforcement of such judgment or order, by reason of a pending
appeal or otherwise, is not in effect.

                           6.9      Attachment by Lenders. Any assets of the
Company or any of its Subsidiaries shall be attached, levied upon, seized or
repossessed, or come into the possession of a trustee, receiver or other
custodian and a determination by any Holder, in good faith but in its sole
discretion, that the same could have a material adverse effect on

<PAGE>

                                                                              14

the prospect for the Holders to fully and punctually realize the full benefits
conferred on the Holders by the Loan Documents.

                           6.10     Adverse Change in Financial Condition. Any
event having a material adverse effect on the business, operations, assets,
properties or condition of the Company and its Subsidiaries taken as a whole
shall have occurred and be continuing or a material adverse effect on the
validity or enforceability of this or any of the other Loan Documents or the
rights or remedies of the Holders hereunder or thereunder.

                  7.       Remedies. Upon and after the occurrence of an Event
of Default, the Holder shall be entitled to the exercise the rights and remedies
set forth in the Security Agreement, the other Loan Documents and under
applicable law, all such rights and remedies being cumulative and enforceable
alternatively, successively or concurrently.

                  8.       Prepayment. The Company may not prepay this Note
prior to the Maturity Date without the prior written consent of the Holders.

                  9.       Seniority. Except as set forth in the Subordination
Agreement, the Notes will rank senior in right of payment to all other
indebtedness of the Company.

                  10.      Assignment. Subject to the restrictions on transfer
described in Section 12 below, the rights and obligations of the Company and
Holder shall be binding upon and benefit the successors, assigns, heirs,
administrators and transferees of the parties. The Company shall not be
permitted to assign this Note without the prior written consent of the Holders.

                  11.      Waiver of Notice. The Company hereby waives notice,
presentment, demand, protest and notice of dishonor.

                  12.      Transfer of This Note. With respect to any offer,
sale or other disposition of this Note, Holder will give written notice to the
Company prior thereto, describing briefly the manner thereof, together with a
written opinion of such Holder's counsel, to the effect that such offer, sale or
other distribution may be effected without registration or qualification (under
any federal or state law then in effect); provided, that no opinion shall be
required for any transfer to an Affiliate or if the transfer is made in
compliance with the Securities Act, so long as the transferee can make the same
representations and warranties at the time of transfer as set forth in Sections
4.5, 4.6, 4.7, 4.8, 4.9, 4.10 and 4.11 of the Purchase Agreement. Promptly upon
delivering such written notice and opinion, if so required, Holder may sell or
otherwise dispose of this Note, all in accordance with the terms of the notice
delivered to the Company. Each Note thus transferred shall bear a legend as to
the applicable restrictions on transferability in order to ensure compliance
with the Securities Act, unless in the opinion of counsel for the Company such
legend is not required in order to ensure compliance with the Securities Act.
The Company may issue stop transfer instructions to its transfer agent in
connection with such restrictions. Notwithstanding the foregoing, the Holder
shall not be permitted to transfer this Note to any Person who is not an
Affiliate until the earlier of (i)

<PAGE>

                                                                              15

the obtaining of Stockholder Approval, (ii) the receipt of written notice from
the Company that Stockholder Approval cannot be obtained, or the occurrence of
an actual vote of the Company's shareholders entitled to vote (whether by
written consent or at a meeting specially called for such purpose), the result
of which is a decision by a majority of the Company's shareholders entitled to
vote to decline to grant Stockholder Approval, (iii) six (6) months from the
date hereof and (iv) the occurrence of an Event of Default.

                  13.      Treatment of Note. To the extent permitted by
generally accepted accounting principles, the Company will treat, account and
report the Note as debt and not equity for accounting purposes and with respect
to any returns filed with federal, state or local tax authorities.

                  14.      Notices. Any notice, request or other communication
required or permitted hereunder shall be in writing and shall be deemed to have
been duly given if personally delivered or if sent by nationally recognized
courier service or mailed by registered or certified mail, postage prepaid, to
the respective addresses of the parties as set forth on the signature pages
hereto or if sent by facsimile to the respective facsimile numbers of the
parties set forth on the signature pages hereto. Any party hereto may by notice
so given change its address for future notice hereunder. Notice shall
conclusively be deemed to have been given and received when personally delivered
or three (3) business days after deposited in the mail or one business day after
sent by courier or upon confirmation of facsimile delivery in the manner set
forth above.

                  15.      No Stockholder Rights. Nothing contained in this Note
shall be construed as conferring upon Holder or any other Person the right to
vote or to consent or to receive notice as a stockholder in respect of meetings
of stockholders for the election of directors of the Company or any other
matters or any rights whatsoever as a stockholder of the Company.

                  16.      Governing Law. This Note shall be governed by and
construed in accordance with the laws of the State of California, excluding that
body of law relating to conflict of laws.

                  17.      Amendments and Waivers. No amendments or waivers of
any provision of this Note, and no consent by the Holder to any departure by the
Company, shall in any event be effective unless the same shall be in writing,
and signed by the Holders of a majority of the outstanding principal amount of
all of the Notes issued by the Company pursuant to the Purchase Agreement, and
then such waiver or consent shall be effective only in the specific instance and
for the purpose for which given.

                  18.      Severability. Any provision of this Note that is
prohibited or unenforceable in a jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

                  19.      WAIVER OF JURY TRIAL. THE COMPANY AND THE

<PAGE>

                                                                              16

HOLDER HEREBY (A) COVENANTS AND AGREES NOT TO ELECT A TRIAL BY JURY OF ANY ISSUE
TRIABLE OF RIGHT BY A JURY, AND (B) WAIVES TRIAL BY JURY IN ANY ACTION OR
PROCEEDING TO WHICH THE COMPANY AND THE HOLDER MAY BE PARTIES, ARISING OUT OF,
IN CONNECTION WITH OR IN ANY WAY PERTAINING TO THIS NOTE, ANY OF THE LOAN
DOCUMENTS AND/OR ANY TRANSACTIONS, OCCURRENCES, COMMUNICATIONS, OR
UNDERSTANDINGS (OR THE LACK OF ANY OF THE FOREGOING) RELATING IN ANY WAY TO
DEBTOR-CREDITOR RELATIONSHIP BETWEEN THE PARTIES. IT IS UNDERSTOOD AND AGREED
THAT THIS WAIVER CONSTITUTES A WAIVER OF TRIAL BY JURY OF ALL CLAIMS AGAINST ALL
PARTIES TO SUCH ACTIONS OR PROCEEDINGS, INCLUDING CLAIMS AGAINST PARTIES WHO ARE
NOT PARTIES TO THIS NOTE. THIS WAIVER OF JURY TRIAL IS SEPARATELY GIVEN,
KNOWINGLY, WILLINGLY AND VOLUNTARILY MADE BY THE COMPANY AND THE HOLDER, AND THE
COMPANY AND THE HOLDER HEREBY AGREE THAT NO REPRESENTATIONS OF FACT OR OPINION
HAVE BEEN MADE BY ANY INDIVIDUAL TO INDUCE THIS WAIVER OF TRIAL BY JURY OR TO IN
ANY WAY MODIFY OR NULLIFY ITS EFFECT. THE COMPANY AND THE HOLDER ARE HEREBY
AUTHORIZED TO SUBMIT THIS NOTE TO ANY COURT HAVING JURISDICTION OVER THE SUBJECT
MATTER AND THE COMPANY AND THE HOLDER, SO AS TO SERVE AS CONCLUSIVE EVIDENCE OF
SUCH WAIVER OF RIGHT TO TRIAL BY JURY. EACH OF THE COMPANY AND THE HOLDER
REPRESENTS AND WARRANTS THAT IT HAS BEEN REPRESENTED IN THE SIGNING OF THIS NOTE
AND IN THE MAKING OF THIS WAIVER BY INDEPENDENT LEGAL COUNSEL, SELECTED OF ITS
OWN FREE WILL, AND/OR THAT IT HAS HAD THE OPPORTUNITY TO DISCUSS THIS WAIVER
WITH COUNSEL.

                  20.      Heading; References. All headings used herein are
used for convenience only and shall not be used to construe or interpret this
Note. Except as otherwise indicated, all references herein to Sections refer to
Sections hereof.

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<PAGE>

                                                                              17

                  IN WITNESS WHEREOF, the Company has caused this Note to be
issued this ___ day of November, 2003.

                                    COMPANY:

                                    CRITICAL PATH, INC.,
                                    a California corporation

                                    By:
                                       ----------------------------------
                                       Name:
                                       Title:

                                       Critical Path, Inc.
                                       532 Folsom Street
                                       San Francisco, CA 94105
                                       Telecopy:  (415) 808-8898
                                       Attention:  Chief Financial Officer

                                       With a copy to:

                                       Pillsbury Winthrop LLP
                                       50 Fremont Street
                                       San Francisco, CA 94105
                                       Telecopy:  (415) 983-1200
                                       Attention:  Gregg Vignos, Esq.

Name of Holder: __________________________

Address:    ______________________________

            ______________________________

Telephone   ______________________________

Facsimile   ______________________________

With a copy to:

Paul, Weiss, Rifkind, Wharton & Garrison LLP
1285 Avenue of the Americas
New York, NY  10019-6064
Attention:  Douglas A. Cifu, Esq.
Telephone:  (212) 373-3436
Fax:  (212) 757-3990