Use this edit to automatically disconnect from Internet Explorer after a specified length of time has elapsed.
Start>Run>Regedit
Go to: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\LanmanServer\Parameters
Modify/Create DWORD Value of Data type REG_DWORD Named [Autodisconnect]
Value Data: [Enter a new disconnect time. Use Hexadecimal if you are unfamiliar with Binary]
Exit Registry / Reboot