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                                                                   EXHIBIT 10.24



                    FIRST AMENDMENT TO THE SERIES C PREFERRED
                            STOCK PURCHASE AGREEMENT


                  THIS FIRST AMENDMENT TO THE SERIES C PREFERRED STOCK PURCHASE
AGREEMENT is made as of the 31st day of December, 2001, by and among USDATA
Corporation, a Delaware corporation (the "Company") and SCP Private Equity
Partners II, L.P., a Delaware limited partnership (the "Investor").

                  WHEREAS, the Company and the Investor are parties to that
certain Series C Preferred Stock Purchase Agreement dated March 30, 2001 (the
"Original Agreement"); and

                  WHEREAS, the Company and the Investor desire to amend the
Original Agreement to provide for an extension of the Company's right to sell
shares of the Option Preferred Stock and to provide the Investor with warrant
coverage for one-half of the Option Preferred Stock purchased by the Investor.

                  NOW THEREFORE, in consideration of the mutual promises
hereinafter set forth, the parties hereto, each intending to be legally bound
hereby, agree as follows:

         1. AMENDMENT TO THE ORIGINAL AGREEMENT.

                           1.1 Amendment to Section 1.4. Section 1.4 of the
Original Agreement shall be renumbered as Section 1.4(a), and a new Section
1.4(b) shall be added reading in its entirety as follows:

                  1.4(b) On the basis of the representations, warranties and
                  agreements herein contained, and upon the terms but subject to
                  the conditions herein set forth and the unanimous approval of
                  all disinterested members of the board of directors of the
                  Company with respect to the acceptance of this commitment by
                  the Investor and the exercise by the Company of its right to
                  sell shares of stock hereunder, the Investor commits to
                  purchase the remaining 21,250 shares of the Option Preferred
                  Stock not purchased under Section 1.4(a) hereof (the
                  "Remainder Stock") at the purchase price of $40.00 per share
                  of Option Preferred Stock at the sole option of the Company.
                  The Company may exercise its right to sell shares of the
                  Remainder Stock on or before December 31, 2002, by means of a
                  written notice therefore to the Investor (each, a "Notice")
                  which certifies (a) the amount of Remainder Stock the Company
                  wishes to sell to the Investor, (b) that the proceeds of the
                  issuance of Remainder Stock will be used solely for general
                  corporate purposes, provided, however, that such proceeds
                  shall not be used, directly or indirectly, for or on account
                  of the settlement or defense of any suit or proceeding brought
                  against the



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                  Company regarding its headquarters' lease agreement (c) that
                  the Company will issue a warrant in favor of the Investor for
                  the purchase of shares of the Company's Series C-2 Preferred
                  Stock in the amount of one-half of the number of Remainder
                  Stock issued. All other conditions and requirements set forth
                  in Section 1.4(a) with respect to the exercise by the Company
                  of its right to sell shares of the Option Preferred Stock
                  shall be inapplicable with respect to the Remainder Stock.
                  Each Notice must be received by the Investor not less than ten
                  (10) business days prior to the desired date of payment. The
                  purchase and sale of the Remainder Stock pursuant to this
                  Section may take place in one or more closings at such times
                  or places as the Company and the Investor may mutually agree
                  (each a "Remainder Closing"). At each Remainder Closing, the
                  Company shall deliver to the Investor a certificate or
                  certificates, registered in the Investor's name, representing
                  such number of shares of Remainder Stock purchasable for the
                  amount of the Purchase Price Installment to be paid to the
                  Company, against payment of such Purchase Price Installment
                  therefore, by check payable to the Company or wire transfer in
                  accordance with the Company's instructions. The Investor's
                  obligation to purchase the Remainder Stock at a Remainder
                  Closing is conditioned upon the Investor's receipt of a
                  certificate, dated as of the date of such Remainder Closing
                  (the "Remainder Closing Date"), and signed by an executive
                  officer of the Company, certifying that the representations
                  contained in Section 2 of this Agreement, are true and correct
                  at and as of such Subsequent Closing Date.

                           1.2 Amendment to Section 2.5. Section 2.5 of the
Original Agreement is hereby amended and restated in its entirety to read as
follows:

                  2.5 Stockholder Approval. Except as otherwise provided in
                  Section 1.4 of the Agreement and Section 1.1 of the Warrant,
                  approval by the stockholders of the Company is not required
                  for the authorization, execution and delivery of this
                  Agreement, the Warrant, and the Second Amended and Restated
                  Investors' Rights Agreement, the performance of all
                  obligations of the Company hereunder and thereunder, and the
                  authorization, issuance (or reservation for issuance) and
                  delivery of the Securities being sold hereunder, the Series C
                  Preferred Stock issuable upon exercise of the Warrant and the
                  Common Stock issuable upon conversion of the Series C
                  Preferred Stock. The Company agrees to use its best efforts to
                  obtain stockholder approval of the transactions contemplated
                  in Section 1.4(a) of the Agreement and Section 1.1 of the
                  Warrant, as soon as practicable, but no later than the date of
                  the Company's next Annual Meeting of Stockholders.

         2. GOVERNING LAW. This Amendment and related agreements, instruments
and documents shall be governed by, and construed and enforced in accordance
with the laws of the State of Delaware, without regard to its otherwise
applicable conflicts of laws rules.


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         3. NON-WAIVER. Except as otherwise expressly set forth herein, this
Amendment does not and shall not be deemed to constitute a waiver by the parties
hereto of any breach or violation of any representation, warranty or covenant
contained in the Original Agreement, and all claims and rights of the
non-breaching party resulting from any such breach or violation are expressly
reserved by such non-breaching party.

         4. INCORPORATION AND REAFFIRMATION. This Amendment shall amend and is
incorporated into and made part of the Original Agreement. To the extent that
any term or provision of this Amendment may be deemed expressly inconsistent
with any term or provision in the Original Agreement, the terms and provisions
of this Amendment shall control. Except as expressly amended by this Amendment,
all of the terms, conditions and provisions of the Original Agreement are hereby
ratified and continue unchanged and remain in full force and effect.

         5. ENTIRE AGREEMENT: Subject to Section 4 above, this Amendment
constitutes the complete understanding of the parties hereto regarding the
subject matter hereof and supersedes any and all other agreements, either oral
or in writing, between the parties hereto with respect to the subject matter
hereof, and no other agreements, either oral or in writing, between the parties
hereto with respect to the subject matter hereof, and no other statement or
promise relating to the subject matter hereof which is not contained herein,
shall be valid or binding.

         6. BINDING EFFECT: This Amendment shall be binding upon and shall inure
to the benefit of the parties hereto and their respective heirs, executors,
administrators, trustees, representatives, successors and permitted assigns.

         7. NO MODIFICATION: No modification of this Amendment or any related
agreements, instruments or documents shall be binding or enforceable unless in
writing and signed on behalf of the party against whom enforcement is sought.

         8. SEVERABILITY: The provisions of this Amendment are to be deemed
severable and the invalidity, illegality or unenforceability of one or more of
the provisions of this Amendment in any jurisdiction shall not affect the
validity, legality or enforceability of the remaining provisions of this
Amendment in such jurisdiction, or the validity, legality or enforceability of
this Amendment, including any such provision, in any other jurisdiction.

         9. HEADINGS: The headings of any section or paragraph of this Amendment
are for convenience of reference only and shall not be used to interpret any
provision of this Amendment.

         10. EXECUTION BY COUNTERPARTS AND FACSIMILE: This Amendment may be
executed in any number of counterparts, each of which when so executed shall be
deemed to be an original and all of which taken together shall constitute one
and the same agreement. Signature by facsimile shall also bind the parties
hereto.



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                  IN WITNESS WHEREOF, the parties have executed this First
Amendment to the Series C Preferred Stock Purchase Agreement as of the date
first above written.



                                  COMPANY:

                                  USDATA CORPORATION



                                  By: /s/  ROBERT MERRY
                                     -------------------------------------------
                                      Robert Merry,
                                      Chief Executive Officer



                                  INVESTOR:

                                  SCP PRIVATE EQUITY PARTNERS II, L.P.

                                  By: SCP Private Equity II General Partner,
                                      L.P., its General Partner

                                  By: SCP Private Equity II LLC,
                                      its Manager



                                  By: /s/ WINSTON J. CHURCHILL
                                     -------------------------------------------
                                  Name:   Winston J. Churchill
                                       -----------------------------------------
                                  Title:
                                        ----------------------------------------