Okay, sorry for the confusion. I guess it's because this is what is confusing me. Everyone saves to the Z drive ... aka, the network drive, but when I look on his computer the network map shows that the Z drive is the external backup hard drive ... it even has the memory icon displayed (just as the C drive has the hard drive icon).

This is a tiny network which consists of two desktop computers, a printer, and a laptop ... as far as I know. I really only looked at the system for about 10 minutes, but I found it confusing that the network drive is also the backup external hard drive????