Weird Inbox Outlook 2010/13 and Exchange

Question

Really weird one this.
I've migrated 7 accounts across from IMAP to Exchange.
5 have migrated across really well.
2 are having problems with the Inbox in Outlook 2010 and 2013.
They both sync all folders to exchange except for the Inbox.
The Inbox show all the emails up to the date of the migration.
But nothing after that.
Using the web OWA does show these latest emails.
So the Outlook Inbox is not syncing with the latest Exchange Inbox.
Any ideas?
I've opened the account using different profiles and different machines with Outlook 2010 but still get the same problem.
Adding the account to an iphone does show the correct Inbox.
FURTHER RESEARCH:
In Outlook 2010 I created a new Folder called "Copy from Inbox"
When a new email arrives, there's a brief period where you see a new email has arrived notice.
I can click on this and I see the new email!
I then move it to the new folder I created above.
I can then see the new emails!
I just can't see them in the Inbox, even though the total count and the unread numbers go up every time a new email arrives.
And this only happens on 2 out of the 7 accounts.
YET MORE RESEARCH :)
In Outlook 2013:
I've labelled my missing emails "test" in the subject line, when I search the current Folder using "test" they are there.
However when I search using Current Mailbox, they disappear.
When I go back to Inbox they disappear.
I'd really appreciate any help, this is driving me insane :(

Answer 1

Unfortunately mailboxes imported to Exchange from IMAP accounts can be a pain as I've found myself! There's a few things that could be causing this.
1) If there's an IMAP filter still being applied to the mailbox, or specifically the inbox that can cause it to not display new mail items. In Outlook 2010 / 2013 I think (I'm looking at Outlook but don't have a mailbox with this issue to check) you
need to go into the View tab, select Change View, Manage Views, and you should see that Filter is set to something. Modify the view and remove the filter. Hopefully that will display the messages again.
2) If that doesn't resolve the issue (or if you see other issues with those mailboxes) check out
http://mellositmusings.com/2012/08/29/exchange-2010-mailboxes-inherit-imap-folder-views-and-attributes-if-imported-from-a-pst-dump-of-an-imap-account/ which goes into detail of how to resolve these issues. The issue I've seen (listed about half way down)
if that the folders retain the container class of IPF.IMAP rather than IPF.Note used by Exchange. You can correct that manually by using MFCMAPI* or if you have Exchange 2010+ you can use EXFolders do update all the folders as a batch.
*Note, if you use MFCMAPI be VERY careful. There's no error checking, you can change / break almost anything in the mailbox and changes are immediately applied, eg no making a change, going "oops", and clicking cancel rather than save.