outlook express 6

Since outlook express 6 is intergrated with XP how to i uninstall it then install..i.e. repair the current installation? My client has a corrupted express..it cannt import messaes from OE6 directory…They need their backed-up mails.
The e-mails can be loaded in other workstations but for security reasons only “THE ONE” computer can hold these mails(privy)…ive tried reinstalling the OS..nothing…i havent tried formating( last option!!!!)

Can Express be isolated from the OS??