I use Outlook 2011 on my MacbookAir. I can confirm no changes have taken place on the MBA or the iPhone. Possible that IT have made some changes on the Exchange server but unlikely.

Until 2 days ago everything was fine. Now though, any reads, deletes etc on messages in my Inbox are not reflected on the server and therefore are not reflected on my iPhone (nor my Windows laptop which I have booted up speficially to help me trouble-shoot).

Changes made on either the PC or the iPhone do propogate to the MBA.

My inbox on the MBA is less than about 20 msgs or so. The inbox is apparently up-to-date. I have deleted a load of messages from both the deleted items and sent items folders which seems to be updating but taking some time.

Any ideas what the problem is?