Archive problem accessing archive folder

[Chaps]

I have recently archived successfully but when I tried to do so again today I
get the error message "The file C:\Documents and Settings\Mike Chappell\Local
Settings\Application Data\Microsoft\Outlook\archive.pst could not be
accessed."

 

[DL]

What version of Outlook?
What size is the Archive file?
Have you run MS Update? (office)