Usually you will receive this message in error. To test, pick up a regular phone and dial your local Vance.Net connection number and see if you hear a high pitched tone. If you do not hear a high pitched tone, please let us know as soon as possible with the number you dialed, and the time it occurred so we can look into it. If you do hear a high pitched tone then go through the below step.
To verify and/or correct the phone number being dialed, click on My Computer, Dial Up Networking then right click on your Vance.Net connection and select properties. Verify and change the phone number if necessary. Remove the check in the box that says use area code and dialing properties. Click ok, close all windows, and try your connection again.
Links to more information:
Error Message "Error 645" Using Dial-Up Networking
Problems connecting at High Speeds with US Robotics 56k WinModem, LT Winmodem or HSP Winmodem.