Do these users have a .pst file along with their Exchange mailbox for mail
storage? Is the meeting in the personal folders rather than the Exchange
mailbox in-box when it is processed? If they are using Personal Folders, do
the missed meetings show in the Personal Folder's Calendar?

Signature
Milly Staples [MVP - Outlook]
Post all replies to the group to keep the discussion intact. All
unsolicited mail sent to my personal account will be deleted without
reading.
After furious head scratching, Krystyna asked:
| When users receive a meeting invitation and they click accept, it
| sends the meeting initiator the accept response but it doesn’t
| always put the meeting into their calendar. Thus people are missing
| meetings because its not showing up in their calendars.