Forty users run the application simulataneously over the LAN without any problems. Only the RDC users have report problems and these are on the terminal server, not the file server. Those problems started immediately after changing from connection string to connection handle. Perhaps it is a coincidence, or due to other software that has also changed. There was a firewall update on Friday, for example. I'm convinced there is more to the story than the facts I've been given thus far.