Outlook 2k msg. is there but not there

Just another weird one, maybe some of you saw this happening. User tells me he got a message print it out, than message disapears from Inbox. I checked, it’s not there, nor in any other folder. User gets another message, see it, half an hour later message is not in Inbox. Now, all this only happens accidentaly, and no, user does not delete or playing games, I do a advanced search for “sender” and “subject contains”, HERE IT IS message is found in Inbox but it’s not showing up on the main screen.

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