HyperTerminal is a serial communicationl program included with Windows.
It is usually found under Start > Programs > Accessories > Communications.

To test the TCP-Com client PC using HyperTerminal, Run Hyperterminal, enter anything as the name for the the connection, click OK, then choose the Modem Name, (which is provided by the Modem Driver which is attached to the TCP-Com Client COM port.). When it asks for a phone number, it's a good idea to use the same phone number that you plan to use for Dial-Up Networking or other dialout application. You may not be able to accomplish much once you get online, but at this will confirm if you are able to successfully make a modem connection to the remote server.

If the dialing fails with a simple error message such as BUSY, NO DIALTONE, etc. then you should proceed to troubleshoot ths just as you would with a local modem. For example, a NO DIALTONE response would indicate that the modem is not plugged into the phone line, or the phone line is producing a proper dialtone. If your phone system requires a 9 to be dialed before generating a Dialtone, this can be overcome by setting "X3" in your modem init string, which tells the modem to dial without waiting for a Dialtone. A BUSY or NO ANSWER response would indicate normal types of issues reaching the phone number that you are attempting to connect to. Try dialing the same number with a voice phone to see if you get the same result.