You can log all information passed between your network connection, the modem, and the remote device, including errors reported by the remote device.
You can view modem commands by enabling logging. After you enable logging, commands sent to the modem are captured in the file systemroot\ModemLog_model.txt. Model is the name of the modem as it appears in the list of installed modems. For instructions about logging modem commands, see To log and view modem commands.