'Modem does not exist' message with Dial-up Networking due to changed modem.
Cause:
The dial-up connection modem was either replaced with a different modem or incorrectly set up.
Solution:
Edit the dial-up networking connection properties and select the correct modem.
1) Double-click the 'My Computer' icon. (The 'My Computer' window appears.)
'My Computer'
2) Double-click the 'Dial-Up Networking' icon.
'Dial-Up Networking'
3) Right-click an existing connection.
Existing connection
4) Select 'Properties' from the pop-up menu.
5) Select a new modem from the 'Connect Using' drop-down list box.
6) Click 'OK'.
