CACHE.DAT is not valid

[Paul1]

I have MS OutLook 2002. Some emails I receive show a
paperclip attachment. When I open the email, no
attachment can be seen. If I click on the attachment
area in the email, I get this message below.

The form cache file 'C:\Documents and
Settings\******\Local Settings\Application
Data\Microsoft\FORMS\CACHE.DAT is not valid.

Any idea what the problem might be?

Thanks,

Paul