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                                                                   Exhibit 10.42

                                                                  March 23, 1999

                                                                     $300,000.00


                             DEMAND PROMISSORY NOTE

                  AMNEX, INC., A New York corporation ("AMNEX") and AMERICAN
NETWORK EXCHANGE, INC., a Delaware corporation and wholly-owned subsidiary of
AMNEX ("ANEI", and together with AMNEX, the "Makers"), for value received,
hereby jointly and severally promise to pay to the order of ROTTERDAM VENTURES,
INC. (the "Holder"), within fifteen (15) days following the date of receipt of
demand for payment (the "Due Date"), at the offices of the Holder indicated in
paragraph 5 hereof the aggregate principal sum of TWO HUNDRED THOUSAND
($300,000.00) DOLLARS in such coin or currency of the United States of America
as at the time of payment shall be legal tender for the payment of public and
private debts and to pay interest on such principal sum from the date hereof at
a fluctuating rate per annum at all times equal to the prime rate of interest
announced from time to time by The Chase Manhattan Bank plus two percent (2%)
(the "Note Rate"). Accrued interest on the unpaid principal balance of this
Demand Promissory Note ("Note") shall be payable on the first business day of
each month commencing May 1, 1999, and on the Due Date.

1.       Registered Owner. The Makers may consider and treat the person in whose
         name this Note shall be registered as the absolute owner thereof for
         all purposes whatsoever (whether or not this Note shall be overdue) and
         the Makers shall not be affected by any notice to the contrary. The
         registered owner of this Note shall have the right to transfer it by
         assignment and the transferee thereof upon his registration as owner of
         this Note, shall become vested with all the powers and rights of the
         transferor. Registration of any new owner shall take place upon
         presentation of this Note to AMNEX at its offices together with an
         assignment duly authenticated. In case of transfers by operation of
         law, the transferee shall notify the Makers of such transfer and of his
         address, and shall submit appropriate evidence regarding the transfer
         so that this Note may be registered in the name of the transferee. This
         Note is transferable only on the books of the Makers by the holder
         hereof in person or by attorney, on the surrender hereof duly endorsed.
         Communications sent to any registered owner shall be effective as
         against all holders or transferees of this Note not registered at the
         time of sending the communication.

2.       Redemption. The Holder, by its acceptance of this Note, hereby
         acknowledges that at any time, and from time to time, notwithstanding
         the lack of demand for payment on the part of the Holder, any of the
         Makers may, at its option, by written notice given to the Holder, elect
         to redeem and prepay all or any portion of the outstanding principal
         indebtedness evidenced by this Note, together with accrued interest
         thereon, without premium or penalty. Any such

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         notice of a Maker's election to redeem and prepay as provided for
         hereinabove shall be given not less than five (5) business days prior
         to the date fixed in such notice as the date for redemption of this
         Note (the "Redemption Date"). Any payments received on this Note shall
         be applied first to any unpaid fees or other sums due and owing
         hereunder, next to accrued but unpaid interest, and then to the
         principal amount outstanding.

3.       Default Rate of Interest: Late Charge. In the event the Makers shall
         fail to pay all or any portion of the principal amount hereof on or
         before the Due Date, any such unpaid amount shall bear interest, for
         each day from the Due Date, until paid in full, at a fluctuating rate
         per annum at all times equal to the Note Rate plus five percent (5%)
         instead of the Note Rate as hereinabove provided, payable upon demand.
         In the event the Makers shall fail to pay timely any other amount due
         hereunder, the Makers, jointly and severally, agree to make a payment,
         in addition to all other required payments hereunder, equal to two
         percent (2%) of the overdue payment.

4.       Applicable Law. This Note is issued under and shall for all purposes be
         governed by and construed in accordance with the laws of the State of
         New York, excluding choice of law rules thereof.

5.       Notices. Any and all notices or other communications or deliveries
         required or permitted to be given or made pursuant to any of the
         provisions of this Note shall be in writing and shall be deemed to have
         been duly given or made for all purposes when hand delivered or sent by
         certified or registered mail, return receipt requested and postage
         prepaid, overnight mail or courier, or telecopier as follows:

         If to Holder at:                   695 Rotterdam Industrial Park
                                            Schenectady, New York 12306-1989
                                            Attention:   David M. Buicko
                                            Telecopier Number: (518) 356-5334

         With a copy to:                    Steven K. Porter, Esq.
                                            695 Rotterdam Industrial Park
                                            Schenectady, New York 12306-1989
                                            Telecopier Number: (518) 357-2534

         If to AMNEX at:                    145 Huguenot Street
                                            New Rochelle, New York 10801
                                            Attention: Chairman
                                            Telecopier Number: (914) 235-1339

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         With a copy to:                    Guy Longobardo, Esq.
                                            145 Huguenot Street
                                            New Rochelle, New York 10801
                                            Telecopier Number: (914) 235-1339

         If to ANEI at:                     100 West Lucerne Circle, Suite 600
                                            Orlando, Florida 32801
                                            Attention:   President
                                            Telecopier Number: (407) 481-2560

         With a copy to:                    Guy Longobardo, Esq.
                                            145 Huguenot Street
                                            New Rochelle, New York 10801
                                            Telecopier Number: (914) 235-1339

         or any such other address as the Holder or any Maker may specify by
         notice given to the other party in accordance with this paragraph 5.

6.       Use of Proceeds. $300,000 is being advanced directly to the Makers from
         the Holder for its general corporate purposes.

7.       Waivers. Makers hereby waive presentment for payment, protest and
         demand, and notice of protest, demand and/or dishonor and nonpayment of
         this Note, and all other notices of demands otherwise required by law
         that Makers may lawfully waive. The Makers expressly agree that this
         Note, or any payment hereunder may be extended from time to time
         without in any way affecting the liability of Makers. No unilateral
         consent or waiver by Holder with respect to any action or failure to
         act which, without consent, would constitute a breach of any provision
         of this Note shall be valid and binding unless in writing and signed by
         Holder.

8.       Consent to Jurisdiction: Jury Trial Waiver. Makers hereby submit to the
         jurisdiction of the courts of the State of New York located in the City
         of Schenectady and the United States District Court for the Northern
         District of New York as well as to the jurisdiction of all courts to
         which an appeal may be taken or other review sought from the aforesaid
         courts, for the purpose of any suit, action or other proceeding arising
         out of Makers obligations under and with respect to this Note, and
         expressly waive any and all obligations they may have as to venue of
         any of such courts. MAKERS AND HOLDER EACH HEREBY WAIVES TRIAL BY JURY
         IN ANY ACTION, PROCEEDING OR COUNTERCLAIM BROUGHT BY EITHER OF THEM
         AGAINST THE OTHER ON ANY MATTERS WHATSOEVER (INCLUDING, WITHOUT
         LIMITATION, ANY ACTION, PROCEEDING OR

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         COUNTERCLAIM ARISING OUT OF OR IN ANY WAY CONNECTED WITH THIS NOTE, OR
         ANY OF THE TRANSACTIONS CONTEMPLATED HEREIN). No party to this Note,
         including but not limited to any assignee of or successor to Makers or
         Holder, shall seek a jury trial in any lawsuit, proceeding,
         counterclaim or any other litigation procedure based upon or arising
         out of this Note or the relationship between the parties. No party will
         seek to consolidate any such action, in which a jury trial has been
         waived, with any other action in which a jury trial cannot be or has
         not been waived. THE PROVISIONS OF THIS PARAGRAPH HAVE BEEN FULLY
         DISCUSSED BY MAKERS AND HOLDER, AND THESE PROVISIONS SHALL BE SUBJECT
         TO NO EXCEPTIONS. NO PARTY HAS, IN ANY WAY, AGREED WITH OR REPRESENTED
         TO ANY OTHER PARTY THAT THE PROVISIONS OF THIS PARAGRAPH WILL NOT BE
         FULLY ENFORCED IN ALL INSTANCES.

9.       Savings Clause. All agreements between Makers and Holder are hereby
         expressly limited so that in no contingency or event whatsoever,
         whether by reason of acceleration of maturity of the indebtedness
         evidenced hereby or otherwise, shall the amount paid or agreed to be
         paid to Holder for the use, forbearance or detention of the
         indebtedness evidenced hereby exceed the maximum permissible under
         applicable law. Any interest received by Holder which would exceed the
         maximum permissible under applicable law shall be applied to the
         reduction of the principal balance evidenced hereby and not to the
         payment of interest. This provision shall control every other provision
         of all agreements between Makers and Holder.

10.      Attorney's Fees. If this Note shall not be paid when due and shall be
         placed by the Holder hereof in the hands of any attorney for
         collection, through legal proceedings or otherwise, the Makers shall
         pay (on demand) all reasonable costs and expenses of collection
         incurred, including reasonable attorneys' fees.

11.      Section Headings. Any section headings in this Note are included herein
         for convenience of reference and shall not constitute a part of this
         Note for any other purpose.

12.      Miscellaneous.

         1.       This Note constitutes the rights and obligations of the Holder
                  and the Makers. No provision of this Note may be modified
                  except by an instrument in writing signed by the party against
                  whom the enforcement of any modification is sought.

         2.       Payment of interest due under this Note prior to the Due Date
                  or Redemption Date, as the case may be, shall be made to the
                  registered holder of this Note. Payment of principal and
                  interest due hereunder on the Due Date or Redemption Date, as
                  the case may be, shall be made to the registered holder of
                  this Note in accordance with the terms hereof following
                  presentation of this Note upon or after such applicable date.
                  No interest shall be due on this Note for such period of time
                  that may elapse between the Due Date or Redemption Date, as
                  the case may be, and its presentation for payment.

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         3.       No recourse shall be had for the payment of the principal of
                  or interest on this Note against any officer, director or
                  agent of any Maker, past, present or future, all such
                  liability of the officers, directors and agents being waived,
                  released and surrendered by the Holder hereof by the
                  acceptance of this Note.

                  IN WITNESS WHEREOF, the Makers have caused this Note to be
signed on its behalf in its corporate name, by its duly authorized officer, all
as of the day and year first above written.

                                   AMNEX, INC.

                                   By:
                                       ---------------------------------
                                   Name:
                                   Title:

                                   AMERICAN NETWORK EXCHANGE, INC.

                                   By:
                                       ---------------------------------
                                   Name:
                                   Title:


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