<PAGE>   1

                                                                   EXHIBIT 10.35

                             SUBSCRIPTION AGREEMENT


TO:  AVANEX CORPORATION

RE:  SUBSCRIPTION FOR AND PURCHASE OF SHARES OF COMMON STOCK

1.   SUBSCRIPTION

     Microsoft Corporation (the "PURCHASER") hereby irrevocably subscribes for
and agrees to purchase, on and subject to the terms and conditions set forth
herein, from Avanex Corporation, a California corporation (the "CORPORATION"),
three hundred eighty-four thousand six hundred fifteen (384,615) shares of
Common Stock of the Corporation (the "SHARES") at a price of $13.00 per share,
having the voting powers, designations, preferences, rights and qualifications
set forth in the Corporation's Restated Certificate of Incorporation, which is
attached hereto as Exhibit "A" (the "RESTATED CERTIFICATE") which is the form of
the Corporation's certificate of incorporation that will govern the Corporation
upon the closing of the Corporation's initial public offering (the "IPO").
Purchaser hereby acknowledges that the Corporation is currently incorporated in
California and is undertaking a reincorporation in Delaware. In connection
therewith, each holder of two shares of capital stock of the California
corporation will receive three shares of the Delaware corporation (the "3-FOR-2
SPLIT"). THE NUMBER OF SHARES SUBSCRIBED FOR HEREIN AND THE SUBSCRIPTION PRICE
(AS DEFINED BELOW) GIVE EFFECT TO THE 3-FOR-2 SPLIT.

2.   PAYMENT

     At Closing, as defined below, the aggregate purchase price for the Shares,
$4,999,995 (the "SUBSCRIPTION PRICE"), shall be paid by wire transfer to the
following account: Coamerica Bank, 55 Almaden Blvd., 2nd Floor, San Jose,
California 95113: ABA No. 121137522; Account No. 1891190538.

3.   DOCUMENTS TO BE PROVIDED BY PURCHASER

     The Purchaser must complete, sign and return as soon as possible, two
executed copies of each of this Subscription Agreement and the Third Amended and
Restated Registration Rights Agreement attached hereto as Exhibit "B"(the
"RIGHTS AGREEMENT").

4.   CLOSING AND DELIVERY OF SHARE CERTIFICATES

     Delivery and payment for the Shares will be completed in one closing (the
"CLOSING") at the offices of Wilson Sonsini Goodrich & Rosati, 650 Page Mill
Road, Palo Alto, California at 8:00 a.m. (Pacific Daylight Time) (the "CLOSING
Time") on such date as the Corporation and the Purchaser may agree (the "CLOSING
DATE"), but in any event not later than February 15, 2000 (unless extended by
mutual agreement of the Corporation and the Purchaser).

<PAGE>   2

         A certificate representing the Shares (the "CERTIFICATE") will be
delivered at Closing against payment to the Corporation of the Subscription
Price in the manner specified in Paragraph 2 above.

5.   CONDITIONS TO CLOSING OF THE PURCHASER

     The Purchaser's obligation to purchase the Shares at the Closing is, at the
option of the Purchaser, subject to fulfillment on or prior to the Closing Date
of the following conditions:

     5.1  Rights Agreement. The Corporation shall have executed and delivered to
the Purchaser the Rights Agreement.

     5.2  Subscription Agreement. The Corporation shall have executed and
delivered to the Purchaser a copy of this Subscription Agreement.

     5.3  Registration Statement. The registration statement filed with the
Securities and Exchange Commission in connection with the Corporation's initial
offering of its securities to the public shall have been declared effective.

6.   CONDITIONS TO CLOSING OF THE CORPORATION

     The Corporation's obligation to issue and sell the Shares at the Closing to
the Purchaser is, at the option of the Corporation, subject to the fulfillment
of the following conditions:

     6.1  Representations and Warranties. The representations and warranties
made by the Purchaser in Section 9 hereof shall be true and correct when made,
and shall be true and correct on the Closing Date with the same force and effect
as if such representations had been made on and as of said date.

     6.2  Subscription Agreement. The Purchaser shall have executed and
delivered to the Corporation a copy of this Subscription Agreement.

     6.3  Payment. The Corporation shall have received from the Purchaser
payment in full for the Subscription Price.

     6.4  Rights Agreement. The Purchaser shall have executed and delivered the
Rights Agreement to the Corporation.

     6.5  Lockup Agreement: The Purchaser shall have executed and delivered a
Lockup Agreement with the Corporation's underwriters in the form of Exhibit "C"
hereto.

7.   REPRESENTATIONS AND WARRANTIES OF THE CORPORATION

     The Corporation hereby represents and warrants to the Purchaser that,
except as otherwise set forth on Exhibit "D" hereto, with specific reference to
the subsection of this Section 7 so affected,


                                      -2-

<PAGE>   3

the following will be true and correct as of the Closing Date (except for the
representation contained in Section 7.3, which is true as of the date hereof):

     7.1  Organization and Standing. The Corporation is a corporation duly
organized and validly existing under, and by virtue of, the laws of the State of
California and is in good standing under such laws. The Corporation has the
requisite corporate power to own and operate its properties and assets and to
carry on its business as presently conducted.

     7.2  Corporate Power. The Corporation has all requisite legal and corporate
power to execute and deliver this Subscription Agreement and the Rights
Agreement, to sell and issue the Shares hereunder and to carry out and perform
its obligations under the terms of this Subscription Agreement and the Rights
Agreement.

     7.3  Capitalization. Giving effect to the stock split effected in
connection with the Corporation's reincorporation into Delaware, the authorized
capital stock of the Corporation consists of 300,000,000 shares of Common Stock,
20,403,456 of which are issued and outstanding and 38,100,000 shares of
Preferred Stock. As of the date hereof, 6,900,000 shares of Preferred Stock have
been designated Series A Preferred, 6,795,120 of which are issued and
outstanding; 9,525,000 shares of Preferred Stock have been designated Series B
Preferred, 9,445,116 of which are issued and outstanding; 16,275,000 shares of
Preferred Stock have been designated Series C Preferred, 13,548,253 of which are
issued and outstanding; and 5,400,000 shares of Preferred Stock have been
designated Series D Preferred, 5,230,646 of which are issued and outstanding.
Effective with the Closing of the IPO, all outstanding Preferred Stock will
convert to Common Stack at a rate of one share of Common Stock for each share of
Preferred Stock. Simultaneously therewith, the Corporation shall file the
Restated Certificate with the Secretary of State of Delaware and the authorized
capital stock of the Company shall consist of 300,000,000 shares of Common
Stock, of which 55,422,591 will be outstanding (assuming (i) no exercise of
options or warrants after December 31, 1999, (ii) the issuance of 6,000,000
shares of Common Stock in the Corporation's IPO, and (iii) no exercise of the
underwriter's over-allotment option in connection with the IPO) and 10,000,000
shares of Preferred Stock, none of which shall be outstanding. The Common Stock
and Preferred Stock have the voting power, designations, preferences, rights and
qualifications set forth in the Restated Certificate. As of December 31, 1999,
except as contemplated herein and except for: (i) the pre-emptive rights granted
pursuant to the Rights Agreement, (ii) options to purchase 3,401,427 shares of
Common Stock of the Corporation granted under its 1998 Stock Plan, and (iii)
warrants to purchase a total of up to 337,500 shares of Common Stock and 29,347
shares of Series D Preferred Stock, there are no options, warrants, conversion
privileges or other rights presently outstanding to purchase or otherwise
acquire any authorized but unissued shares of the capital stock or other
securities of the Corporation, nor any agreements or understandings with respect
thereto.

     7.4  Financial Statements. As of the Closing Date, the Corporation will
have delivered to the Purchaser the audited financial statements of the
Corporation as of December 31, 1999 (the "FINANCIAL STATEMENTS"). The Financial
Statements, together with the notes thereto, are complete and correct in all
material respects, have been prepared in accordance with generally accepted
accounting principles consistently applied throughout the periods covered
thereby, and present fairly the financial position of the Corporation as of
their respective dates. Other than as


                                      -3-

<PAGE>   4

described in the Financial Statements, the Corporation has no material
liabilities and knows of no material contingent liabilities not disclosed in the
Financial Statements, except current liabilities incurred in the ordinary course
of business which are not, individually or in the aggregate, materially adverse.

     7.5  Authorization. All corporate action on the part of the Corporation,
its directors and stockholders necessary for the authorization, execution,
delivery and performance of this Agreement and the Rights Agreement, the
authorization, sale, issuance and delivery of the Shares and the performance of
the Corporation's obligations hereunder and thereunder has been taken or will be
taken prior to the Closing. This Agreement and the Rights Agreement when fully
executed and delivered by the Corporation, shall constitute valid and binding
obligations of the Corporation, enforceable in accordance with their respective
terms, subject to laws of general application relating to bankruptcy, insolvency
and the relief of debtors and rules of law governing specific performance,
injunctive relief or other equitable remedies. The Shares, when issued in
compliance with the provisions of this Agreement, will be validly issued, fully
paid and non-assessable, and free of any liens or encumbrances; provided,
however, that the Shares may be subject to certain restrictions on transfer
under applicable state and/or Federal securities laws.

     7.6  Governmental Consents, etc. No consent, approval or authorization of
or designation, declaration or filing with any state or federal governmental
authority on the part of the Corporation is required in connection with the
valid execution and delivery of this Agreement, the Rights Agreement or the
offer, sale or issuance of the Shares, or the consummation of any other
transaction contemplated hereby, except qualification (or taking such action as
may be necessary to secure an exemption from qualification, if available) under
the California Corporate Securities Law and other applicable blue sky laws, of
the offer and sale of the Shares, which filing and qualification, if required,
will be accomplished in a timely manner prior to or promptly after the Closing.

     7.7  Registration Rights. At the closing, except as set forth in the Rights
Agreement, the Corporation will not be under any obligation to register any of
its presently outstanding securities, or any of its securities which may
hereafter be issued, under the Securities Act of 1933, as amended (the
"SECURITIES ACT").

     7.8  Brokers or Finders. The Corporation has not incurred, and will not
incur, directly or indirectly, any liability for brokerage or finders' fees or
agents' commissions or any similar charges in connection with this Agreement or
any transaction contemplated hereby.

     7.9  No Conflict. The offer and sale of the Shares by the Corporation and
the performance and consummation of the transactions contemplated herein will
not conflict with or result in (i) a breach or violation of any of the terms or
provisions of, or constitute a default under, any indenture, mortgage, deed of
trust, loan agreement or other agreement (written or oral) or instrument to
which the Corporation is bound or to which any of the property or assets of the
Corporation is subject, which breach or violation or the consequences thereof
would result in a Material Adverse Effect, (ii) any violation of the provisions
of the Restated Certificate, the by-laws or any resolutions of the Corporation
or (iii) to the Corporation's knowledge a violation of any statute or any order,
rule or regulation of any court or governmental agency or body having
jurisdiction over the Corporation or


                                      -4-

<PAGE>   5

any of its assets or properties, which violation or the consequences thereof
would result in a Material Adverse Effect.

8.   CERTAIN MATTERS RELATING TO THE OFFER AND SALE OF THE SHARES

     The Purchaser acknowledges and agrees that: (i) it has not been provided
with a registration statement, prospectus or any similar document in connection
with its purchase of the Shares and (ii) its decision to execute this Agreement
and the Rights Agreement and to purchase the Shares has not been based upon any
verbal or written representations as to fact or otherwise made by or on behalf
of the Corporation and that its decision is based upon the information,
representations and covenants of the Corporation contained in this Agreement,
its own review of certain of the Corporation's documents and records, and
publicly available information concerning the Corporation.

9.   REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE PURCHASER

     The Purchaser hereby represents, warrants and covenants to the Corporation
(which representations, warranties and covenants shall survive the Closing) as
of the date hereof and as of the Closing Date as follows:

     9.1  Experience; Risk. The Purchaser has such knowledge and experience in
financial and business matters that it is capable of evaluating the merits and
risks of the purchase of the Shares pursuant to this Agreement and is capable of
protecting its interests in connection herewith. The Purchaser has the ability
to bear the economic risk of the investment, including complete loss of the
investment.

     9.2  Investment. The Purchaser is acquiring the Shares for investment for
its own account, not as a nominee or agent, and not with a view to, or for,
resale in connection with any distribution thereof, and the Purchaser has no
present intention to sell, grant any participation in, or otherwise distribute
the Shares. The Purchaser understands that the Shares have not been registered
under the Securities Act and will be issued pursuant to an exemption from the
registration requirements thereof, which exemption depends upon, among other
things, the bona fide nature of the investment intent and the accuracy of such
Purchaser's representations as expressed herein.

     9.3  Rule 144. The Purchaser understands that the Shares are "restricted
securities" under Federal securities laws, as they are unregistered and are
being acquired from the Corporation in a transaction not involving a public
offering, and that under such laws and applicable regulations promulgated
thereunder the Shares may be resold without registration under the Securities
Act only in certain limited circumstances. The Purchaser acknowledges that the
Shares must be held indefinitely unless subsequently registered under the
Securities Act or an exemption from such registration is available. The
Purchaser is aware of the provisions of Rule 144 promulgated under the
Securities Act, the provisions of which limit resale of "restricted securities."


                                      -5-

<PAGE>   6

     9.4  No Public Market. The Purchaser understands that no public market now
exists for the Shares or for any other securities issued by the Corporation and
that there is no assurance that a public market will ever exist for the Shares.

     9.5  Authorization.

          (a)  The Purchaser has the full right, power and authority to enter
into and perform its obligations under this Agreement and the Rights Agreement.
This Agreement and the Rights Agreement when executed and delivered by the
Purchaser, will constitute valid and binding obligations of the Purchaser,
enforceable in accordance with their respective terms, subject to the laws of
general application relating to bankruptcy, insolvency and the relief of
debtors, rules of law governing specific performance, injunctive relief and
other equitable remedies.

          (b)  The Purchaser further represents that it is a validly existing
corporation, has the necessary corporate capacity and authority to execute and
deliver this Agreement and to observe and perform its covenants and obligations
hereunder and has taken all necessary corporate action in respect thereof.

     9.6  Further Limitations on Disposition. Without in any way limiting the
representations set forth above, the Purchaser further agrees not to make any
offer or sale of all or any portion of the Shares within the United States or to
a U.S. resident unless and until:

          (a)  There is then in effect a Registration Statement under the
Securities Act covering such proposed offer or sale and such offer or sale is
made in accordance with such Registration Statement; or

          (b)  The Purchaser shall have notified the Corporation of the proposed
offer or sale and shall have furnished the Corporation with a statement of the
circumstances surrounding the proposed disposition, and if reasonably requested
by the Corporation, such Purchaser shall have furnished the Corporation with an
opinion of counsel, reasonably satisfactory to the Corporation, that such offer
or sale is exempt from the registration requirements under the Securities Act.

          (c)  Notwithstanding the provisions of paragraph (b) above, no such
registration statement or opinion of counsel shall be necessary for a transfer
by Purchaser to any transferees in transactions contemplated by paragraph (b)
above, if all such transferees agree in writing to be subject to the terms
hereof to the same extent as if they were Purchasers hereunder.

     9.7  Legends. It is understood that each certificate representing the
Shares, and any securities issued in respect thereof or exchange therefor shall
bear legends substantially in the following form (in addition to any legend
required under applicable state securities laws):

          "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
          REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND HAVE BEEN
          ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION WITH,
          THE SALE OR DISTRIBUTION THEREOF. SUCH SECURITIES MAY NOT BE SOLD OR
          TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION


                                      -6-

<PAGE>   7

          UNLESS THE CORPORATION RECEIVES AN OPINION OF COUNSEL REASONABLY
          ACCEPTABLE TO IT STATING THAT SUCH SALE OR TRANSFER IS EXEMPT FROM THE
          REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SAID ACT. COPIES
          OF THE AGREEMENTS COVERING THE PURCHASE OF THESE SECURITIES AND
          RESTRICTING THEIR TRANSFER MAY BE OBTAINED AT NO COST BY WRITTEN
          REQUEST MADE BY THE HOLDER OF RECORD OF THIS CERTIFICATE TO THE
          SECRETARY OF THE CORPORATION AT THE PRINCIPAL EXECUTIVE OFFICES OF THE
          CORPORATION.

          THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A LOCKUP
          PERIOD OF UP TO 180 DAYS FOLLOWING THE EFFECTIVE DATE OF THE FIRST
          REGISTRATION STATEMENT OF THE COMPANY FILED UNDER THE SECURITIES ACT
          OF 1933, AS AMENDED, AS SET FORTH IN AN AGREEMENT BETWEEN THE ISSUER
          AND THE ORIGINAL HOLDER OF THESE SECURITIES, A COPY OF WHICH MAY BE
          OBTAINED AT NO COST BY WRITTEN REQUEST MADE BY THE HOLDER OF RECORD OF
          THIS CERTIFICATE TO THE SECRETARY OF THE CORPORATION AT THE PRINCIPAL
          EXECUTIVE OFFICES OF THE CORPORATION. SUCH LOCKUP PERIOD IS BINDING ON
          TRANSFEREES OF THESE SECURITIES."

     9.8  Accredited Investor Status. The Purchaser presently does, and will as
of the Closing Date, qualify as an "accredited investor" within the meaning of
Rule 501(a) promulgated under the Securities Act.

     9.9  Brokers or Finders. The Purchaser has not incurred, and will not
incur, directly or indirectly, any liability for brokerage or finders' fees or
agents' commissions or any similar charges in connection with this Agreement or
any transactions contemplated hereby.

     9.10 [Intentionally Omitted]

     9.11 [Intentionally Omitted]

     9.12 Solicitation of Proxies. Purchaser will not participate in any
solicitation of proxies with respect to the voting of Company Securities.

     9.13 Notice. Purchaser shall notify the Corporation of Purchaser's
acquisition of any Company Securities within 15 days prior to such acquisition
and all such acquisitions shall comply with federal and state securities laws.

     9.14 Control Group. Purchaser shall not form or participate in a "group"
(as defined in Rule 13d-5 of the Exchange Act) with respect to any Company
Securities.


                                      -7-

<PAGE>   8

10.  RELIANCE UPON REPRESENTATIONS, WARRANTIES AND COVENANTS

     The Purchaser acknowledges that the representations and warranties and
covenants contained in this Agreement are made with the intent that they may be
relied upon by the Corporation to, among other things, determine its eligibility
to purchase the Shares. The Purchaser further agrees that by accepting the
Shares, the Purchaser shall be representing and warranting that the foregoing
representations and warranties are true as of the Closing with the same force
and effect as if they had been made by the Purchaser at the Closing.

11.  COSTS

     The Purchaser acknowledges and agrees that all costs and expenses incurred
by the Purchaser (including any fees and disbursements of any counsel retained
by the Purchaser) relating to the offer and sale of the Shares to the Purchaser
shall be paid by the Purchaser.

12.  GOVERNING LAW

     This Agreement shall be governed in all respects by the laws of the State
of California.

13.  SURVIVAL

     This Agreement, including without limitation the representations,
warranties and covenants contained herein, shall survive and continue in full
force and effect and be binding upon the parties notwithstanding the completion
of the purchase of the Shares by the Purchaser pursuant hereto, or any
subsequent disposition by the Purchaser of the Shares.

14.  ASSIGNMENT

     This Agreement is not transferable or assignable by the parties hereto.

15.  ENTIRE AGREEMENT; AMENDMENT

     This Agreement, the Exhibits hereto, and the other documents delivered
pursuant hereto constitute the full and entire understanding and agreement among
the parties with regard to the subjects hereof and thereof. Neither this
Agreement nor any term hereof may be amended, waived, discharged or terminated
other than by a written instrument signed by the Purchaser and the Corporation.

16.  NOTICES, ETC.

     All notices and other communications required or permitted hereunder shall
be in writing and shall be deemed effectively given upon personal delivery; upon
confirmed transmission by telecopy


                                      -8-

<PAGE>   9

or telex; or seven (7) days following deposit with the United States Post
Office, by registered or certified mail, postage prepaid, addressed: (a) if to
the Purchaser, at One Microsoft Way, Redmond, Washington 98052-6399, or its
telecopy number or telex number or at such other address as such Purchaser shall
have furnished to the Corporation in writing, or (b) if to the Corporation, at
40919 Encyclopedia Circle, Fremont, California 94538, or its telecopy or telex
number, addressed to the attention of the President, and with a copy to Wilson
Sonsini Goodrich & Rosati, 650 Page Mill Road, Palo Alto, California 94304,
Attention: Judith M. O'Brien, or at such other address as the Corporation shall
have furnished to the Purchaser in writing.

17.  DELAYS OR OMISSIONS.

     No delay or omission to exercise any right, power or remedy accruing to any
holder of any Common Stock, upon any breach or default of the Corporation under
this Agreement, shall impair any such right, power or remedy of such holder, nor
shall it be construed to be a waiver of any such breach or default, or an
acquiescence therein, or of or in any similar breach or default thereafter
occurring, nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of any
holder of Common Stock of any breach or default under this Agreement, or any
waiver on the part of such holder of any provisions or conditions of this
Agreement, must be in writing and shall be effective only to the extent
specifically set forth in such writing. All remedies, either under this
Agreement or by law or otherwise afforded to any such holder, shall be
cumulative and not alternative.

18.  SEVERABILITY

     In the event that any provision of this Agreement becomes or is declared by
a court of competent jurisdiction to be illegal, unenforceable or void, this
Agreement shall continue in full force and effect without said provision;
provided that no such severability shall be effective if it materially changes
the economic benefit of this Agreement to any party.

19.  COUNTERPARTS

     This Agreement may be exercised in counterparts, each of which shall be
deemed to be an original and all of which shall constitute one and the same
document.

20.  TERMINATION

     This Agreement shall terminate and be of no further force and effect, and
the rights of the Purchaser and the Corporation hereunder shall terminate if the
registration statement filed in connection with the Corporation's IPO shall not
have been declared effective by the Securities and Exchange Commission on or
before March 31, 2000.


                                      -9-

<PAGE>   10

     EXECUTED at __________, this 14th day of January, 2000.


                                        MICROSOFT CORPORATION



                                        By: /s/ JOHN CONNORS
                                           -------------------------------------
                                        (Signature of Authorized Representative)


                                        John Connors
                                        ----------------------------------------
                                        (Name of Person Signing)


                                        SUP-CFO
                                        ----------------------------------------
                                        Office or Title


                                      -10-

<PAGE>   11

                                   ACCEPTANCE

     The above-mentioned Subscription Agreement is hereby accepted and agreed to
by Avanex Corporation.

     EXECUTED at Fremont, California, the 14th day of January, 2000.



                                        AVANEX CORPORATION



                                        By: /s/ WALTER ALESSANDRINI
                                           -------------------------------------


                                      -11-