Few users changed company to another and they had exported pst file from old account. Now the pst file is imported to another Exchange 2010 server and the mail items, calendar items, contacts etc. can be seen on the clients Outlook.
However old calendar items doesn't sync to mobile devices. When creating new it works without an issue. Items created on different server won't sync. Same when forwarding appointment to someone you will get and error. Or when trying to modify calendar item created on old server. Any ideas how to change items so user can modify the old items also. Only deleting is working for items created on different server.