This is because the processing within the mail store is being done on the mail server itself. Moving folders in webmail moves the items almost instantaneously. I know for certain you can move folders in Exchange 2010. Folder creation and movement should be done via webmail.

The best method to organezize (Taxi Driver reference) is to move individual items (by date or whatever you choose) within Outlook itself. Divide the mail up by year, by quarter, or even by month if you have that much mail. Keep all folders item counts below 5,000, including the number of items in subfolders. With new hosted Exchange providers exclaiming with pride about “unlimited mail storage”, you’ll be forced to organize in order to avoid breakage. That is, unless a system admin limits mail store size to something abominably low so this issue is avoided altogether. New users currently engaged in an Exchange –> Mac setup should follow this main guideline. Granted most will already have a mailbox in despair and cannot conform to this easily, it should be noted that it can be fixed. Despite no documentation stating there is a limit for Mac 2011, it’s apparent that reducing mailbox size can drastically improve performance and minimize downtime. Keeping them under 5,000 or so items seems to keep things in shape. Namely, the inbox and sent items folders. Item Count Limitation: One of the biggest culprits (seemingly) is the high number of items users tend to have in their mail folders. Here is where this article will come to your aid. Various reports from numerous forums (both Microsoft and non-Microsoft) indicate a variety of ways to combat this. Why this pertains to Outlook 2011 on the latest supported version of Exchange (2010) is unknown, but the existence of the issue is undeniable. There is no “official” Microsoft documentation stating this but older documentation for Exchange 20 explains issues regarding mail store parsing by mail clients.

The problem is a communication issue between the mail client and the mail server. The issues vary from mail not syncing at all to delayed and intermittent mail retrieval from the Exchange server to mail disappearing and just about everything in between.

There have been numerous cases reported of Outlook 2011 for Mac not syncing properly with Exchange (bis NOT supported by Outlook for Mac).

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