In order to limit the cause of failure it is possible to activate the checkbox Record log in Control Panel/Modems/Settings/Settings/Extended. With activated logging a log file is generated in the Windows directory, e.g. C:\WINNT. The name of the file depends on the modem, e.g.:ModemLog_Sportster 28800-33600 External.txt. In this file all data are logged, which are exchanged with the modem. Only activate this option for a short time, because the file quickly gets very big.