Hi,
Disable autodisconnect http://support.microsoft.com/default.aspx?scid=kb;en-us;297684&Product=win2000
UNC mapping has similar problems, but there is also a fix for that.

>I have a server. This one has a map drive to a secondary server. That map drive is set to reconnect at login. So, basically, this map drive should live permanently, even if the server reboots.
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>However, on one location, if I reboot the secondary server, the main server will reconnect the map drive once the secondary becomes available. But, this will only live for a few hours or days. I then have to go in Explorer, disconnect the drive and reconnect again. This will again run into the same situation. The only way to resolve that issue is to always have the main server to reboot about the secondary server has been rebooted. Following that order, the server will never loose its map drive connection with the secondary server and that can live for months.
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>Normally, this should not be the case. Even if the secondary server reboots, once rebooted, the server having a map drive to it should see and reconnect to the drive.
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>Has anyone seen that? Does anyone know a way to avoid that other than the brut force reboot of the server having a map drive to the secondary server?
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>The server having the map drive and the secondary sever are both Windows Server 2003.