MPREXE not responding

When logging on to our NT domain using Win95 clients, several users have to wait several minutes before logon will complete. If durring this time, you hit , you see MPREXE (not responding). Our solution in the past has been to “reset” that user’s profile by replacing the user.dat file on their home directory and delete the local profile and all cookies and history on the machine. This would solves the problem untilthe user logs on to a different machine that changes the user registry and once again causes MPREXE to not respond. Does anyone know how to fix this for good?