One of the recent requests from a user stated that all his mail without even visiting Inbox went right into … Deleted Items folder. No problem – just find the rule which does that and remove or fix it.
Simple as “one, two, three, doesn’t work”. Yep, after I had deleted all the rules the Inbox still lacked the mail.
Now what? Moving mailbox to another location? Probably that would help, probably not, but it is not a solution, actually (neither was the workaround we have found).
Even Google Almighty wasn’t able to find the solution (I found it later, when I new what to look for), so we went to our final resort: Microsoft Premier Support (yep, we didn’t want to breed a new variety of users: those who read their email in deleted items and store business critical documents in the recycled bin). The workaround was quite simple: set AutomateProcessing for the mailbox into AutoUpdate. After doing that:
Get-Mailbox | Set-CalendarProcessing -AutomateProcessing AutoUpdate
everything went back to normal. And you know what? I’m fine with it, even it wasn’t me, who found the solution =)