I have a Windows XP PC in a Windows 2003 domain and if I leave the PC on
overnight my mapped drives get disconnected.  Is there a setting somewhere
that does this, something like a timeout value or a keep alive?  Any help or
insight on keeping my drives constantly mapped is greatly appreciated.

Yes, there is a setting on the server you need to change.

Apparently, drives 'disconnecting' shouldn't cause problems, but sometimes
it does.

http://support.microsoft.com/?kbid=297684

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