I have a client that I do a little work for every now and then. I have been called in previously about a couple of PCs all of a sudden not being able to connect to shared folders on the server. I changed cables and stop the machine from going to sleep etc. I never heard back and presumed that all was ok, but it wasn't.
First thing in the morning and occasionally through the day (when away from the machines) this seems to happen. However it doesn't affect access to printers or the internet. So I would believe that it would have something to do with the way the server was setup. Is there a lease time function that I should be looking at?