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                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                   FORM 12b-25

                                               Commission File Number 1-14896

                           NOTIFICATION OF LATE FILING

(Check One):   [_] Form 10-K    [_] Form 11-K    [_] Form 20-F    [X] Form 10-Q
               [_] Form N-SAR

          For Period Ended:  September 30, 2005
          [_]  Transition Report on Form 10-K
          [_]  Transition Report on Form 20-F
          [_]  Transition Report on Form 11-K
          [_]  Transition Report on Form 10-Q
          [_]  Transition Report on Form N-SAR

          For the Transition Period Ended:______________________________________

     Read attached  instruction  sheet before  preparing  form.  Please print or
type.

     Nothing in this form shall be  construed to imply that the  Commission  has
verified any information contained herein.

     If the  notification  relates  to a portion of the  filing  checked  above,
identify the item(s) to which the notification relates: ________________________


                                     PART I
                             REGISTRANT INFORMATION

Full name of registrant  NETWORK-1 SECURITY SOLUTIONS, INC.

Former name if applicable

________________________________________________________________________________

Address of principal executive office (Street and number)

445 Park Avenue, Suite 1028
________________________________________________________________________________

City, state and zip code

New York, New York  10022
________________________________________________________________________________

                                    PART II
                             RULE 12b-25(b) AND (c)

     If the subject report could not be filed without unreasonable effort or
expense and the registrant seeks relief pursuant to Rule 12b-25(b), the
following should be completed. (Check box if appropriate.)

       |  (a)  The reasons described in reasonable detail in Part III of this
       |       form could not be eliminated without unreasonable effort or
       |       expense;
       |  (b)  The subject annual report, semi-annual report, transition report
       |       on Form 10-K, 20-F, 11-K or Form N-SAR, or portion thereof will
  [X]  |       be filed on or before the 15th calendar day following the
       |       prescribed due date; or the subject quarterly report or
       |       transition report on Form 10-Q, or portion thereof will be filed
       |       on or before the fifth calendar day following the prescribed due
       |       date; and
       |  (c)  The accountant's statement or other exhibit required by Rule
       |       12b-25(c) has been attached if applicable.


                                    PART III
                                    NARRATIVE

     State below in reasonable detail why the Form 10-K, 11-K, 20-F 10-Q, N-SAR
or the transition report portion thereof could not be filed within the
prescribed time period. (Attach extra sheets if needed.)

     On November 14, 2005, the Company completed certain issues pertaining to
its financial statements included in its Form 10-QSB for the quarterly period
ended September 30, 2005, including the restatement of its financial statements
for the nine month period ended September 30, 2004. As soon as all issues
pertaining to the 10-QSB were resolved, at approximately 5:15 p.m. on November
14, 2005 the Company attempted to file its 10-QSB for the quarterly period ended
September 30, 2005 with the Securities and Exchange Commission. After the filing
deadline (5:30 p.m.) the Company was advised by its outside filing service that
the 10-QSB was not accepted for filing by 5:30 p.m. and was deemed filed on
November 15, 2005.

                                    PART IV
                               OTHER INFORMATION

(1)  Name and telephone number of person to contact in regard to this
     notification

     Corey M. Horowitz, Chairman & CEO               (212)        829-5700
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                       (Name)                     (Area Code) (Telephone Number)

(2)  Have all other periodic reports required under Section 13 or 15(d) of the
     Securities Exchange Act of 1934 or Section 30 of the Investment Company Act
     of 1940 during the preceding 12 months or for such shorter period that the
     registrant was required to file such report(s) been filed? If the answer is
     no, identify report(s).
                                                                 [X] Yes  [_] No

(3)  Is it anticipated that any significant change in results of operations from
     the corresponding period for the last fiscal year will be reflected by the
     earnings statements to be included in the subject report or portion
     thereof?
                                                                 [_] Yes  [X] No

     If so: attach an explanation of the anticipated change, both narratively
and quantitatively, and, if appropriate, state the reasons why a reasonable
estimate of the results cannot be made.

                       NETWORK-1 SECURITY SOLUTIONS, INC.
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                  (Name of Registrant as Specified in Charter)

Has  caused  this  notification  to be signed on its  behalf by the  undersigned
thereunto duly authorized.


Date: November 15, 2005        By /s/ Corey M. Horowitz
      -----------------           ---------------------------------------------
                                  Name: Corey M. Horowitz
                                  Title: Chairman and Chief Executive Officer


     INSTRUCTION: The form may be signed by an executive officer of the
registrant or by any other duly authorized representative. The name and title of
the person signing the form shall be typed or printed beneath the signature. If
the statement is signed on behalf of the registrant by an authorized
representative (other than an executive officer), evidence of the
representative's authority to sign on behalf of the registrant shall be filed
with the form.