Error message "Message cannot be found" in one WM folder

I have several folders for mail and suddenly one of the folders appears to
have become corrupt. All the message headers are still present but all
message bodies read "Message cannot be found".

An internet search reveals that some anti-virus programs can cause this - I
am running Windows Security Essentials but can't see how this could suddenly
have occurred.

I checked in the message store and that particular folder does not seem to
exist any longer. I do so hope it may be possible to retrieve the messages
and any advice will be gladly received. Running Vista (fully up to date) and
Windows Mail 6.0.6000.16386.

Many thanks,

Ian

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