I agree with Joe K. Another re-install attempt over what's already there is likely to completely destroy any files or fragments that survive. When files are "invisible" to an OS they exist until the space the reside in is over-written. That's why file recovery is possible. The only initial...
I seem to recall that Outlook and Outlook Express actually use different file names for things personal address books, personal folders, etc. (As do different versions of those programs. Ah, Microsoft. :)) I would do a scan, not for "outlook.pst" but simply for "*.pst" for personal folders...