Unable to open COMX

“Unable to open com port COMX”

This message occurs when HyperTerminal Private Edition attempts to use a communications port, either for a modem connection or a direct cabled connection, but receives an error report from the Windows operating system. The Windows TAPI device may not be functioning properly.

To initiate a connection, HTPE makes a programming request through Windows TAPI, Telephony Application Programming Interface, to the attached device. TAPI is the intermediary between software applications that need the use of communications hardware devices. A communications software, such as HTPE, requests Windows TAPI to open the designated serial port, send commands to the device, then pass control of the device back to the application that requested its use. This occurs when a successful connection has been established. In this case, Windows was unable to access and open the selected communications port. It could not open the desired port and reported the failure to HTPE, which displayed the message listed above.

This is a hardware/operating system issue that is resolved through either:

Removing the device and reinstalling it through Device Manager in the Systems icon in Control Panel; or

Reinstalling Windows TAPI from your installation CD.