No dial tone. Check phone line connection. If modem is plugged into a phone line splitter, remove it and try connecting the line directly to a telephone wall jack. Cannot contact Internet provider with recommended AT command string. Check with your Internet provider for requirements.
Characters appear twice on screen.
Communication software not set up for full duplex operation. Incomprehensible characters appear on screen. Data bit, parity, and stop bit settings are incorrect. Not Found Use the communications software s auto-search function to determine if your system can communicate with the modem. If the system cannot communicate with it, the modem will have to be reconfigured.