Modem with network registration doesn´t ping


I am trying to solve a problem related to GPRS. I have developed a program that works with a GPRS conection. The ME has IP and it is attached to the network according to at command responses but communication doesn´t work. Does anybody found this problem before?

Thank you.

There surely is no wavecom developer who hasn’t encountered that problem. Could you be a little more specific?

Sorry, explanation must be a little short.

My system is based on an field equipment with a Q24Plus Modem connected to a Front End. The problem found is that, after a perfect boot and exchange of GPRS data, a few of the modems ( 3 out of 200 aprox. ) do not reply to any question of the Front End. Even a response to “ping” is not received. A Customer Application developed with Open AT is running always in the modem. In this case, when a Modem fails to communicate, program is running perfectly and any at comand question by the serial port stands that everything about net registration, gprs registration, network attachment is working well.