If you are using a dial-up or a broadband modem (as distinct from a router), check that the INternet connection in your PC isn't set up to close the connection automatically.
Go to "Start",
then "Control Panel",
select "Classic View",
select "Internet Options",
select "Connections" tab,
select "Settings" (to the right of Dial Up and Virtual
Private Network Setings Window).
Click on "Advanced" and see if the "Disconnect if idle for..." box is ticked.
Untick it to disable the auto timeout or change the time to a value you prefer.
If you're using a router, there may be a timeout in that. RTFM
John, August 2008