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                                                                    Exhibit 10.5



                              CARRY PROMISSORY NOTE

September 7, 2001                                                      $170,347


                  Ken S. Bajaj ("MAKER"), hereby promises to pay to the order of
DigitalNet Holdings, Inc. (the "COMPANY"), the aggregate unpaid principal amount
of this Note, together with interest thereon calculated from the date hereof in
accordance with the provisions of this Note.

                  This Note is one of the promissory notes referred to in the
Senior Management Agreement, dated as of September 7, 2001, by and among the
Company, DigitalNet, Inc., a Delaware corporation, and Maker (the "MANAGEMENT
AGREEMENT"). Sections 1(a)(ii) and 1(b)(i) of the Management Agreement contain
provisions for the issuance of this Note upon the terms and conditions specified
therein. Capitalized terms used herein and not otherwise defined shall have the
meanings given to them in the Management Agreement.

                  1. ACCRUAL OF INTEREST. Interest shall accrue on the
outstanding principal amount of this Note at a rate equal to the lesser of (i)
5% per annum and (ii) the highest rate permitted by applicable law, compounded
annually.

                  2. PAYMENT OF PRINCIPAL AND INTEREST ON NOTE.

                  (a) SCHEDULED PAYMENTS. Executive shall repay the principal
amount and interest of this Note in 36 equal monthly installments of the
principal amount of this Note (i.e., $4,732) (plus the accrued interest on such
principal amount being repaid) on the last day of each full calendar month
beginning with the first full calendar month following the date hereof.

                  (b) MANDATORY PREPAYMENTS. Upon a Liquidity Event, Maker shall
pay the entire principal amount then outstanding and any accrued interest to the
Company. In addition, in the event Maker, or any of his permitted transferees,
receives any net cash proceeds in connection with the Carried Stock (whether
held by Maker or one or more of Maker's permitted transferees, other than the
Company and the Investors (as defined in the Management Agreement)), Maker shall
prepay (up to an amount equal to the principal amount and interest on the
portion of this Note relating to such Carried Stock for which net cash proceeds
are received) any amounts owed pursuant to this Note by applying all of such
proceeds FIRST, to any accrued interest and SECOND, to any principal then
outstanding.

                  (c) OPTIONAL PREPAYMENTS. Maker may, at any time and from time
to time without premium or penalty, prepay all of the outstanding principal
amount of the Note; provided that any prepayment will be accompanied by a
payment of accrued interest on the portion being prepaid. A prepayment of less
than all of the outstanding principal amount of the

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Note shall not relieve Maker of his obligation to make the payments on the Note
pursuant to Sections 2(a) and 2(b) above.

                  (d) RIGHT OF OFFSET. The Maker shall be entitled to offset any
amounts owed to the Maker by the Company, now existing or hereinafter arising,
pursuant to and as set forth in Section 4 of the Management Agreement between
the Company and the Maker, against any amounts payable under this Note.
Following an Event of Default, the Company shall be entitled to offset any
amounts owed to the Company by the Maker, now existing or hereinafter arising,
pursuant to this Note against any amounts payable by the Company to the Maker
pursuant to and as set forth in the Management Agreement between the Company and
the Maker.

                  (e) RECOURSE. Notwithstanding anything herein or in any other
agreement, instrument or other document to the contrary, the Maker shall be
personally liable for 100% of the repayment of the indebtedness evidenced by
this Note or for any claim of any kind based thereon.

                  3. EVENTS OF DEFAULT.

                  (a) DEFINITION. For purposes of this Note, an Event of Default
shall be deemed to have occurred if:

                           (i) Maker fails to pay when due, the full amount of
         any principal or interest payment, and such amount remains unpaid for 2
         business days following receipt of written notice from the Company; or

                           (ii) Maker makes an assignment for the benefit of
         creditors or admits in writing his inability to pay his debts generally
         as they become due; or an order, judgment or decree is entered
         adjudicating Maker bankrupt or insolvent; or any order for relief with
         respect to Maker is entered under the Federal Bankruptcy Code; or Maker
         petitions or applies to any tribunal for the appointment of a
         custodian, trustee, receiver or liquidator of any substantial part of
         Maker's assets, or commences any proceeding relating to Maker under any
         bankruptcy, reorganization, arrangement, insolvency, readjustment of
         debt, dissolution or liquidation law of any jurisdiction; or any such
         petition or application is filed, or any such proceeding is commenced,
         against Maker and either (A) Maker by any act indicates its approval
         thereof, consent thereto or acquiescence therein or (B) such petition,
         application or proceeding is not dismissed within 60 days.

                  (b) CONSEQUENCES OF EVENTS OF DEFAULT. If an Event of Default
has occurred the aggregate principal amount of the Note (together with all
accrued interest thereon and all other amounts payable in connection therewith)
shall become immediately due and payable without any action on the part of the
Company, and Maker shall immediately pay to the Company all amounts due and
payable with respect to the Note.

                  Maker, or his successors and assigns, hereby waives diligence,
presentment, protest and demand and notice of protest and demand, dishonor and
nonpayment of this Note,


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and expressly agrees that this Note, or any payment hereunder, may be extended
from time to time and that the Company may accept security for this Note or
release security for this Note, all without in any way affecting the liability
of Maker hereunder.

                  In the event that Maker fails to pay any amounts due hereunder
when due, Maker shall pay to the Company, in addition to such amounts due, all
costs of collection, including, without limitation, reasonable attorneys fees.

                  4. AMENDMENT AND WAIVER. Except as otherwise expressly
provided herein, the provisions of the Note may be amended and Maker may take
any action herein prohibited, or omit to perform any act herein required to be
performed by it, only if Maker has obtained the written consent of the Company.

                  5. CANCELLATION. After all principal and accrued interest at
any time owed on this Note has been paid in full, this Note shall be surrendered
to Maker for cancellation and shall not be reissued.

                  6. PLACE OF PAYMENT. Payments of principal and interest are to
be delivered to the Company at the following address:

                           DigitalNet Holdings, Inc.
                           6700A Rockledge Drive, Suite 525
                           Bethesda, MD 20817
                           Attention:  President and Chief Executive Officer

or to such other address or to the attention of such other person as specified
by prior written notice to Maker.

                  7. USURY LAWS. It is the intention of the Company and Maker to
conform strictly to all applicable usury laws now or hereafter in force, and any
interest payable under this Note shall be subject to reduction to the amount not
in excess of the maximum legal amount allowed under the applicable usury laws as
now or hereafter construed by the courts having jurisdiction over such matters.
If the maturity of this Note is accelerated by reason of an election by the
Company resulting from an Event of Default, voluntary prepayment by Maker or
otherwise, then earned interest may never include more than the maximum amount
permitted by law, computed from the date hereof until payment, and any interest
in excess of the maximum amount permitted by law shall be canceled automatically
and, if theretofore paid, shall at the option of the Company either be rebated
to Maker or credited on the principal amount of this Note, or if this Note has
been paid, then the excess shall be rebated to Maker. The aggregate of all
interest (whether designated as interest, service charges, points or otherwise)
contracted for, chargeable, or receivable under this Note shall under no
circumstances exceed the maximum legal rate upon the unpaid principal balance of
this Note remaining unpaid from time to time. If such interest does exceed the
maximum legal rate, it shall be deemed a mistake and such excess shall be
canceled automatically and, if theretofore paid, rebated to Maker or credited on
the principal amount of this Note, or if this Note has been repaid, then such
excess shall be rebated to Maker.

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                  8. GOVERNING LAW. This Note is made under and governed by the
internal law, not the laws of conflicts, of the State of Delaware.


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                  IN WITNESS WHEREOF, Maker has executed and delivered this Note
as of the date above.




                                                   /s/ KEN S. BAJAJ
                                                   ------------------------
                                                   KEN S. BAJAJ


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