Fix Error 678 on Modem Dialing

Dial Up Networking Error 678: The computer you are dialing did not answer

Error 678 generally means that the line is ringing, but the remote system is not answering the call. Check the number being called and verify that the number is correct.
If using an external modem, turn on the speaker to listen to the connection using the toggle switches on the modem chassis. The exact behavior will vary from modem to modem, so check the modem manufacturer’s manual.

Symptoms
User receives Error 678: The computer you are dialing did not answer.
Cause
The modem is unable to establish a dial up connection due to certain conditions.
Resolution

1. Is there a modem handshake sound? If not the telephone access number is probably wrong in some way.
2. Disable Area Code and Dialing Properties. If the area code and Dialing properties are set incorrectly, this error may results.
3. Try lowering the fifo buffers, setting the max speed to 57600 in your modems settings.
4. Try adding several commas after the access number. eg: 570-555-5555,,,