Lost Internet Connection !

If you was able to connect , and ISP software is installed correctly .check the following:

Check modem is enabled in system bios
Check modem is listed correctly in windows device manager and that there is no "X" meaning device disabled or faulty or "!" meaning wrong or missing device drivers.
If modem is listed twice in device manager . remove both devices and reboot your system a plug and play modem will be reconfigured on next system restart.
Look at modem properties ,under diagnostic's tab use query modem button to see if the modem will respond . If it does not ,you may have a conflict of hardware IRQ's .make sure the modem has its own IRQ and is not beening shared with some other device.
Check phone line has dialling tone . check the line with a voice call or alternately have BT run a line check.
Check modem lead .Try using a spare lead instead !
In internet properties under connections tab ,check that your dial up internet connection is listed and that "Always dial default connection" is selected.
Try several phone numbers to connect ,in case ISP has changed the access numbers
Try to connect with a slower port speed to start with if connection is successful then increase speed.

Note

The default maximum port speed is 115200 ,this can sometimes be too fast if phone line is bad .Lowering speed will sometimes allow pages to load faster in your browser ,even though the connection speed may be slower.