NT4.0 workstation.

we are running peer to peer networking with various type of operating systems ranging from windows 2000 to win 98. on some nt4.0 workstations machines if we change the network identification of the machine all files for the previous user under the profiles directorys vanish such as excel files which we had saved in a folder the the user tamela desktop. these shoud not vanish just becuase we rename the network id. any one else experienced this?