Copy from Network Problem

I have a smal business Network , and one of the computers

can't copy the files from a shared folder (folder ADV ) in the Server.

( 5 computers)

The "problem computer" , can copy anything from and to

anywhere , but when it copies from folder ADV in the Server ,

I get the message that "network path is no longer valid "

All running WinXP Pro , SP2 The drives are not

mapped ( and even when I try to Map them I get the same message )

I formatted the "problem computer " , and the message

still comes back .

Scandisked Sever and the remaining 4 computer .

There is no Firewall ( Internal Network )

All other computers copying to and from any shared folder

normally .

Hints ?