Contract number: [ complete Service contract conditions of December 2018  The parties agree that any communication made by email has full legal effect and is  admissible as evidence in judicial proceedings.  Any communication is deemed to have been made when the receiving party receives it, unless  this contract refers to the date when the communication was sent.  E-mail is deemed to have been received by the receiving party on the day of dispatch of that  e-mail, provided that it is sent to the e-mail address indicated in Article I.8. The sending party  must be able to prove the date of dispatch. In the event that the sending party receives a non- delivery report, it must make every effort to ensure that the other party actually receives the  communication by email or mail. In such a case, the sending party is not held in breach of its  obligation to send such communication within a specified deadline.  Mail sent to the contracting authority is deemed to have been received by the contracting  authority on the date on which the department responsible referred to in Article I.8 registers it.  Formal notifications  are considered to have been received by the receiving party on the date  of receipt indicated in the proof received by the sending party that the message was delivered  to the specified recipient. If provided for in the special conditions, the exchange of electronic documents (e-documents)  such as invoices between the parties is automated through the use of the  e-PRIOR  platform.  This platform provides two possibilities for such exchanges: either through web services  (machine-to-machine connection) or through a web application (the  supplier portal ). The contracting authority takes the necessary measures to implement and maintain electronic  systems that enable the  supplier portal  to be used effectively. In the case of machine-to-machine connection, a direct connection is established between the  parties’  back offices . In this case, the parties take the measures necessary on their side to  implement and maintain electronic systems that enable the machine-to-machine connection to  be used effectively. The electronic systems are specified in the  interface control document .  The contractor (or leader in the case of a joint tender) must take the necessary technical  measures to set up a machine-to-machine connection and at its own cost.  If communication via the  supplier portal or via the web services (machine-to-machine  connection) is hindered by factors beyond the control of one party, it must  notify the other  immediately and the parties must take the necessary measures to restore this communication. If it is impossible to restore the communication within two working days, one party must  notify the other that alternative means of communication specified in Article II.5.1 will be  used until the  supplier portal  or the machine-to-machine connection is restored. When a change in the  interface control document requires adaptations, the contractor (or  leader in the case of a joint tender) has up to six months from receipt of the  notification  to  implement this change. This period can be shortened by mutual agreement of the parties. This  period does not apply to urgent measures required by the security policy of the contracting  authority to ensure integrity, confidentiality and non-repudiation of information and the  availability of  e-PRIOR , which must be applied immediately. II.5.3 Submission of e-documents via e-PRIOR  II.5.2 Date of communications by mail and email  17 