One of my office users is having this problem in his outlook 2013, which is setup in exchange cache mode. Everyday when he opens outlook, it shows downloading around 3.5GB of emails. This is happening even after he completes downloading all of the emails. On my part I deleted his old outlook profile and reconfigured a new one and let the outlook download all the mailbox again. Once it finished downloading, it is showing the same everyday.
Any solution for this? And why this may be happening?
I saw this one more thread with similar issue, but it was left inconclusive.
http://answers.microsoft.com/en-us/msoffice/forum/msoffice_outlook/outlook-downloads-entire-mailbox-35-gb-again/5935c330-40a6-46c4-b43f-fa74ec52a32f