Running Outlook 2003 and ran into this error this morning trying to
accept an updated meeting request. Never seen it before - seems others
have run into the same problem and no one had a fix.

I tried /cleanfreebusy switch - no effect
I tried /cleandmrecords switch - no effect
I tried /cleanreminders switch - no effect

Looking at the meeting request, it was an update to a meeting set
several months ago. On a whim, I went in and deleted the old meeting
request series and then tried to accept the one in my inbox this
morning.

It worked! So, this may be a fix/work-around for those stuggling with
this error. If it's an updated meeting request - go back and delete
the series of meetings it is replacing and then accept the updated
request.

YMMV.
Russ