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                                                                   EXHIBIT 10.20

                         REGISTRATION RIGHTS AGREEMENT

     THIS REGISTRATION RIGHTS AGREEMENT is made as of June 14, 2000, by and
between McAfee.com Corporation, a Delaware corporation (the "COMPANY"), and the
undersigned stockholders (the "STOCKHOLDERS") of Tufans Technology Corp., a
corporation organized under the laws of the State of Delaware ("Tufans
Technology").

                                    RECITALS

     WHEREAS, concurrent with delivery of this Agreement, the Company, Tufans
Technology, the Stockholders and the Escrow Agent are entering into a Share
Purchase Agreement on the date hereof (the "PURCHASE AGREEMENT") which provides
for the purchase (the "PURCHASE") of all of the issued and outstanding shares
of Tufans Technology by the Company in exchange for cash and shares of Company
Class A Common Stock;

     WHEREAS, as an inducement to the Stockholders to enter into the Purchase
Agreement, as of the Closing Date, the shares of Company Class A Common Stock
that are issued to the Stockholders pursuant to the Purchase Agreement shall be
granted registration rights as set forth herein; and

     WHEREAS, all terms not otherwise defined herein shall have the same
meanings ascribed to them in the Purchase Agreement;

     NOW, THEREFORE, THE PARTIES HEREBY AGREE AS FOLLOWS:

     1.   Registration Rights. The Company covenants and agrees as follows:

          1.1  Definitions. For purposes of this Section 1:

               (a)  The term "Act" means the Securities Act of 1933, as amended.

               (b)  The term "1934 Act" shall mean the Securities Exchange Act
of 1934, as amended.

               (c)  The term "register", "registered," and "registration" refer
to a registration effected by preparing and filing a registration statement or
similar document in compliance with the Act, and the declaration or ordering of
effectiveness of such registration statement or document.

               (d)  The term "Registrable Securities" means the Class A Common
Stock of the Company ("Common Stock") issued to the Stockholders in accordance
with the terms and conditions of the Purchase Agreement, including any escrowed
Common Stock, and any issued as a dividend on or other distribution with respect
to, or in exchange for or replacement of, such common stock.

               (e)  The term "SEC" shall mean the Securities and Exchange
Commission.

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        1.2     Obligations of the Company. Whenever required under this
Section 1 to effect the registration of any Registrable Securities, the Company
shall, as soon as reasonably practicable:

                (a)  Upon written request by Stockholders holding more than 70%
of the total Registrable Securities then held by Stockholders, but in any event
no sooner than 270 days following the Closing, provided the Company is then
eligible to do so under the Act and the 1934 Act, and provided that the
Registrable Securities that are subject to such written request are not
eligible for resale without volume limitation pursuant to Rule 144, 144A or
145, prepare and file with the SEC as soon as reasonably practicable (but,
subject to the provisions below, no more than 60 days from the date of the
Stockholder request), a registration statement on Form S-3 with respect to all
Registrable Securities (hereinafter referred to as the "Registration
Statement"); provided, however, that the Company may delay such filing for a
period of up to 90 days if, after consultation with counsel, the Company
determines in good faith that the filing of a Registration Statement would be
detrimental to the Company and the Company delivers a certificate to the
Stockholders stating the reasonable basis of the delay. The Company may invoke
this privilege no more than twice. Upon filing the Registration Statement, the
Company will use commercially reasonable efforts to cause such registration
statement to become effective as soon as reasonably possible thereafter, and,
subject to the provisions below, use its reasonable best efforts to keep such
registration statement effective for a period of 180 days or, if earlier, until
the Stockholders have sold all of the Registrable Securities. If at any time
after a registration statement becomes effective, the Company advises the
Stockholders in writing that due to any stop order or the existence of material
information that has not been disclosed to the public and included in the
registration statement it is necessary to amend the registration statement, the
Stockholders shall suspend any further sale or Registrable Securities pursuant
to the Registration Statement until the Company advises the Stockholders that
such stop order has been lifted or the registration statement has been amended.
In such event, the Company shall use reasonable efforts to cause such stop
order to be lifted or the registration statement to be amended promptly,
provided that the Company shall not be required to amend the registration
statement during any time when the Company's officers and directors are
prohibited from buying or selling the Company's Common Stock pursuant to the
Company's insider trading policy. Notwithstanding the foregoing sentence, the
Company shall file any amendment necessary for the Stockholders to recommence
sales under the registration statement concurrently with the commencement of
any period in which directors and officers of the Company are allowed to buy or
sell Common Stock pursuant to the Company's insider trading policy. In
addition, the Company may suspend use of the Registration Statement to the
extent the Company is advised by its legal counsel that such action is
reasonably necessary to comply with federal securities law. In the event the
sales of Registrable Securities of the Stockholders are suspended as provided
above, the 180-day period during which a registration statement must be kept
effective shall be extended for the total number of days during which sales are
suspended.

                (b)  Subject to subsection 1.2(a), notify the Stockholders upon
becoming aware of the need to file, and prepare and file with the SEC such
amendments and supplements to such Registration Statement and the prospectus
used in connection with such Registrable Statement as may be necessary to
comply with the provisions of the Act with respect to the disposition of all
securities covered by such Registration Statement.



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                  (c)      Furnish to the Stockholders and their underwriters,
if any, such numbers of copies of a prospectus, including a preliminary
prospectus, in conformity with the requirements of the Act, and such other
documents as the Stockholders may reasonably request in order to facilitate the
disposition of Registrable Securities owned by them.

                  (d)      Use commercially reasonable efforts to register and
qualify the securities covered by such registration statement under such other
United States securities or Blue Sky laws of such jurisdictions as shall be
reasonably requested by the Stockholders, provided that the Company shall not be
required in connection therewith or as a condition thereto to qualify to do
business or to file a general consent to service of process in any such states
or jurisdictions, unless the Company is already subject to service in such
jurisdiction and except as may be required by the Act.

                  (e)      The Company may include securities issued in
connection with any acquisition not otherwise registered on a Registration
Statement on Form S-4 in the registration pursuant to this Agreement.

                  (f)      Comply with all other material requirements of the
Act, the 1934 Act, or any rule and regulation promulgated under the Act or the
1934 Act.

         1.3      Information from Stockholders. It shall be a condition
precedent to the obligations of the Company to take any action pursuant to this
Section 1 with respect to the Registrable Securities of the Stockholders that
the Stockholders shall furnish to the Company such information regarding
themselves, the Registrable Securities held by them, and the intended method of
disposition of such securities, as shall be required to effect the registration
of the Registrable Securities.

         1.4      Expenses of Registration. All expenses of any registration,
including (without limitation) all registration, filing and qualification fees,
printers' and accounting fees, fees and disbursements of counsel for the Company
shall be borne by the Company; provided, however, that the Company shall not be
required to pay any professional fees of the Stockholders other than the fees of
one counsel to the Stockholders (not to exceed $5,000 in the aggregate).

         1.5      Indemnification. In the event any Registrable Securities are
included in the Registration Statement under this Section 1:

                  (a)      The Company will indemnify and hold harmless each of
the Stockholders, each of their directors, officers, trustees or beneficiaries,
if applicable and each person, if any, who controls a non-individual Stockholder
within the meaning of the Act against any losses, claims, damages, or
liabilities (joint or several) to which any of the Stockholders may become
subject under the Act or the 1934 Act or other federal or state law, insofar as
such losses, claims, damages, or liabilities (or actions in respect thereof)
arise out of or are based upon any of the following statements, omissions or
violations (collectively a "Violation"): (i) any untrue statement or alleged
untrue statement of a material fact contained in the Registration Statement,
including any preliminary prospectus or final prospectus contained therein or
any amendments or supplements thereto, (ii) the omission or alleged omission to
state therein a material fact required to be stated therein, or necessary to
make the statements therein not misleading, or (iii) any


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violation or alleged violation by the Company of the Act, the 1934 Act, or any
rule or regulation promulgated under the Act, or the 1934 Act; and the Company
will pay to each of the Stockholders as incurred any legal or other expenses
reasonably incurred by such Stockholder in connection with investigating or
defending any such loss, claim, damage, liability, or action; provided, however,
that the indemnity agreement contained in this subsection 1.5(a) shall not apply
to amounts paid in settlement of any such loss, claim, damage, liability, or
action if such settlement is effected without the consent of the Company, which
consent shall not be unreasonably withheld or delayed, nor shall the Company be
liable in any such case to any Stockholder for any such loss, claim, damage,
liability, or action to the extent that it arises out of or is based upon a
Violation which occurs in reliance upon and in conformity with information
furnished in writing expressly for use in connection with such registration by
such Stockholder seeking indemnification hereunder. In addition, the Company
shall not be liable for any untrue statement or omission in any prospectus if a
supplement or amendment thereto correcting such untrue statement or omission was
delivered to the Stockholders prior to the pertinent sale or sales by the
Stockholders.

               (b)  Each Stockholder will indemnify and hold harmless the
Company, each of its directors, each of its officers who has signed the
Registration Statement, each person, if any, who controls the Company within the
meaning of the Act, any other Stockholder selling securities in such
Registration Statement and any controlling person of any such Stockholder,
against any losses, claims, damages, or liabilities (joint or several) to which
any of the foregoing persons may become subject, under the Act, or the 1934 Act
or other federal or state law, insofar as such losses, claims, damages, or
liabilities (or actions in respect thereto) arise out of or are based upon any
Violation, in each case to the extent (and only to the extent) that such
Violation occurs in reliance upon and in conformity with written information
furnished by such Stockholder expressly for use in connection with such
registration; and such Stockholder will pay, as incurred, any legal or other
expenses reasonably incurred by any person intended to be indemnified pursuant
to this subsection 1.5(b), in connection with investigating or defending any
such loss, claim, damage, liability, or action; provided, however, that the
indemnity agreement contained in this subsection 1.5(b) shall not apply to
amounts paid in settlement of any such loss, claim, damage, liability or action
if such settlement is effected without the consent of such Stockholder, which
consent shall not be unreasonably withheld or delayed; provided, that, in no
event shall the aggregate indemnity under this subsection 1.5(b) by such
Stockholder exceed the gross proceeds from the offering received by such
Stockholder.

               (c)  Promptly after receipt by an indemnified party under this
Section 1.5 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 1.5, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that an indemnified party
(together with all other indemnified parties which may be represented without
conflict by one counsel) shall have the right to retain one separate counsel,
with the fees and expenses to be paid by the indemnifying party, if
representation of such indemnified party by the counsel retained by the
indemnifying party would be inappropriate due to action or potential

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differing interests between such indemnified party and any other party
represented by such counsel in such proceeding. The failure to deliver written
notice to the indemnifying party within a reasonable time of the commencement of
any such action, if prejudicial to its ability to defend such action, shall
relieve such indemnifying party to the extent of any liability to the
indemnified party under this Section 1.5, but the omission so to deliver written
notice to the indemnifying party will not relieve it of any liability that it
may have to any indemnified party otherwise than under this Section 1.5.

               (d)  If the indemnification provided for in this Section 1.5 is
held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any loss, liability, claim, damage, or expense referred to
therein, then the indemnifying party, in lieu of indemnifying such indemnified
party hereunder, shall contribute to the amount paid or payable by such
indemnified party as a result of such loss, liability, claim, damage, or expense
in such proportion as is appropriate to reflect the relative fault of the
indemnifying party on the one hand and of the indemnified party on the other in
connection with the statements or omissions that resulted in such loss,
liability, claim, damage, or expense as well as any other relevant equitable
considerations. The relative fault of the indemnifying party and of the
indemnified party shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission to state a material fact relates to information supplied by the
indemnifying party or by the indemnified party and the parties' relative intent,
knowledge, access to information, and opportunity to correct or prevent such
statement or omission.

               (e)  The obligations of the Company, and the Stockholders under
this Section 1.5 shall survive the completion of any offering of Registrable
Securities in a registration statement under this Section 1, and otherwise.

          1.6  Reports Under the Securities Exchange Act. The Company agrees to
use commercially reasonable efforts to file with the SEC in a timely manner all
reports and other documents and information required of the Company under the
1934 Act, and take such other actions as may be necessary to assure the
availability of Form S-3 for use in connection with the registration rights
provided in this Agreement.

          1.7  Rules 144 and 144A. The Company shall use commercially reasonable
efforts to file the reports required to be filed by it under the Act and the
1934 Act in a timely manner and, if at any time the Company is not required to
file such reports, it will, upon the written request of any Stockholder, make
publicly available other information so long as necessary to permit sales of the
Stockholders' securities pursuant to Rule 144 and 144A. The Company covenants
that it will take such further action as the Stockholders may reasonably
request, all to the extent required from time to time to enable the Stockholders
to sell securities without registration under the Act within the limitation of
the exemptions provided by Rules 144 and 144A (including the requirements of
Rule 144A(d)(4)).

     2.   Miscellaneous.

          2.1  Notices. All notices and other communications hereunder shall be
in writing and shall be deemed given if delivered personally or by commercial
delivery service, or mailed by registered or certified mail (return receipt
requested) or sent via facsimile (with

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acknowledgment of complete transmission) to the parties at the following
addresses (or at such other address for a party as shall be specified by like
notice):

          (1)  if to the Company:

               2805 Bowers Avenue
               Santa Clara, CA 95051
               Attention: General Counsel
               Facsimile No.: (408) 572-1560


          (2)  if to the Stockholders, to:

               Mr. Matthew J. Feldman
               1065 First Place, S.E.
               Issaquah, WA 98027
               Tel: (425) 427-5082
               Fax: (425) 427-5083

               with a copy to:

               Greenberg Traurig, LLP
               200 Park Avenue -- 15th Floor
               New York, NY 10166
               Attn: Spencer G. Feldman, Esq.
               Tel: (212) 801-9200
               Fax: (212) 801-6400

          2.2 Interpretation. The words "include," "includes" and "including"
when used herein shall be deemed in each case to be followed by the words
"without limitation." The headings contained in this Agreement  are for
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

          2.3 Counterparts. This Agreement may be executed in one or more
counterparts, all of which shall be considered one and the same agreement and
shall become effective when one or more counterparts have been signed by each
of the parties and delivered to the other party, it being understood that all
parties need not sign the same counterpart.

          2.4 Entire Agreement; Assignment. This Agreement and the documents
and instruments and other agreements among the parties hereto referenced
herein; (a) constitute the entire agreement among the parties with respect to
the subject matter hereof and supersede all prior agreements and
understandings, both written and oral, among the parties with respect to the
subject matter hereof; (b) are not intended to confer upon any other person any
rights or remedies hereunder; and (c) without the prior written consent of each
party shall not be assigned by operation of law or otherwise. Any assignment of
rights or delegation of duties under this Agreement by a party without the
prior written consent of the other parties.


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          2.5  Severability. In the event that any provision of this Agreement
or the application thereof, is declared by a court of competent jurisdiction to
be illegal, void or unenforceable, the remainder of this Agreement will continue
in full force and effect and the application of such provision to other persons
or circumstances will be interpreted so as reasonably to effect the intent of
the parties hereto. The parties further agree to replace such void or
unenforceable provision of this Agreement with a valid and enforceable provision
that will achieve, to the extent possible, the economic, business and other
purposes of such void or unenforceable provision.

          2.6  Other Remedies. Except as otherwise provided herein, any and all
remedies herein expressly conferred upon a party will be deemed cumulative with
and not exclusive of any other remedy conferred hereby, or by law or equity upon
such party, and the exercise by a party of any one remedy will not preclude the
exercise of any other remedy.

          2.7  Governing Law. This Agreement shall be governed by and construed
in accordance with the laws of the State of Delaware, regardless of the laws
that might otherwise govern under applicable principles of conflicts of laws
thereof.

     IN WITNESS WHEREOF, the parties have executed this Registration Rights
Agreement as of the date first above written.

                                        MCAFEE.COM CORPORATION


                                        By: /s/ GREGORY P.G. WHARTON
                                            ---------------------------------
                                            Gregory P.G. Wharton,
                                            General Counsel and
                                            Director of Corporate Development

                                        Address:  2805 Bowers Avenue
                                                  Santa Clara, CA 95051-0963


                                        STOCKHOLDERS

                                        By:
                                            ---------------------------------

                                        Its:
                                            ---------------------------------









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