Ok, my user rebooted overnight, came back in today and the issue has
gone.

However, other things you could try

- clear free busy data (run outlook with the cleanfreebusy switch, that
is, in the command prompt with outlook closed, run c:\program
files\......(wherever your office and outlook is located)\outlook.exe
/clearfreebusy

- check that he hasn't by mistake delegated someone else to accept
meeting requests on his behalf and in turn removed himself.




--
invers