We have drive mappings via login script to map CIFS drives with proper
convention (ServerName-w) and things are working. But periodically when
users try to access one of these CIFS drives they will be prompted to log
in again. And no matter what they enter it will complain the name and pw
do not match.

This only happens periodically, and to different servers. If they do a
regular drive mapping they are fine. What do we miss here? Thanks.