If you try to connect to the Internet using Microsoft Internet Explorer 4, and get a message telling me the modem isn’t working you may need to test the modem.
First double-click My Computer and then double-click Dial-Up Networking. Next double-click the Connection icon and click Connect. If your modem works and you successfully connect to your ISP, you need to check IE 4 to make sure you told it to use the correct connection.
If you can’t connect using the Connection dialog box, you might have a modem problem, or you may have set your connection to an incorrect ISP (perhaps an earlier one).
To see if your modem is responding, click Start, Settings, Control Panel. When the Control Panel opens, double-click the Modems icon. Now click the Diagnostics tab in the Modems Properties dialog box. Click your modem entry to select it, then click More Info. If all is well, the program reports the modem parameters.
If your modem is OK, you may have told IE 4 to use the wrong modem (perhaps a modem you had installed previously).