An Error Occured while reconnecting

Each time I want to save something om my “H” (mapping) drive on the Server, I get the next message:

A error occured while reconnecting. Microsoft Windows Network: The local device name is already in use. The connection has not been restored.

I can access the mapping through exploring “My network places”. I have tried another map network drive, but it does the same thing. It seems that only the Windows XP PC’s are doing it.

Please advice.