I keep getting the error message

Outlook Express could not be started. The application was unable to open the
Outlook Express message store. Your computer may be out of memory or your
disk is full. Contact Microsoft support for further assistance. (0x80004005,
183)

But when it shows, OE is running and sends and received fine. The only thing
I've altered recently is that I've installed Office 2007.
OS is XP, OE is version 6.2