Janelle wrote:

I have Outlook Express on my system and was trying to upgrade to
Outlook.

Outlook is not an upgrade for Outlook Express. They are independent
applications with different functions (although there is some overlap,
obviously).

When I installed the new program I attempted to import my
address book from Outlook Express.

What version of Outlok? How did you try to import? You should use
FileImport and Export?Import Internet Mail and Addresses.

I instead imported an old address
book that was on an Excel spreadsheet that I had from when I
purchased the computer a few years ago. Now I cannot find my Express
address book. I located my pst file per previous similar questions &
replies, relocated it and reopened it in Outlook Express. It still
contains the old address book. Is my address book still retrievable?

That all depends on the exact steps you took to get where you are and you
haven't described them in enough detail to know.
--
Brian Tillman