Can't Use Outlook after changing Servers

[Dave Mackler]

Moved users from one server to another. Users map USER folder to U:\ drive,
no chnage there. After move when trying to open Outlook it stops with an
error that there is a security problem with the .pst file. There is none I
can find. Tried deleting Outlook profile for user and installing a new one,
came up with same pst file. tried adding a second pst file and get the same
security violation, No other files have problems, WORD or Excel.

ideas??

dave Admin