I've had the following problems on multiple Windows networks (using domains) which have a password expiration policy:
After a while the user can't access network resources. This seems to be caused by the fact that the users password has expired, however s/he isn't notified about the fact that the password expired, even after multiple logins/logouts/reboots. Manually changing the password always resolves the issue. The machines are running up-to-date Windows XP. An other commonality seems to be that the given machines are rebooted rarely (once or twice a week).
While it is good to have a workaround, I would be interested in eliminating the source of the problem. Does anyone know what might be the root cause of this?
PS. A problem, which might or might not be related, is that some shares are only available when using their IP rather than their name...
"some shares are only available when using their IP rather than their name" - The shares not working, have you tried if the computer can resolve the name just doing ping "name" from cmd?
Also, the ones that ARE working, maybe because they might be on the computer's host file?
When the computer cant access network resources, try running a program called kerbtray. It will show the computer's kerberos tickets and you will be able to see if the computer lost connection with the domain controller.