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Please contact us if you need ideas for a more distributed Mac Apple Mail archive solution. As a general practice, syncing programs like Busy Sync are not recommended because of their latent instability once the program enters an irrecoverable failure mode.
There are is also a known issue with Apple Mail for users with tons and tons of emails. Users with historical emails going back years should consider archiving emails older than say 5 years and taking those emails permanently offline. Both the size of emails and sheer quantity (hundreds of thousands) can cause Apple Mail to pinwheel or not properly display or locate those emails in searches. Sometimes it can take a really long time for those emails to come up. For the Exchange email system, the only client program that can successfully handle this kind of quantity (hundreds of thousands) of emails is Microsoft Outlook 2010 or later on Windows 7 or 8.
Outlook 2011 on Macs
With few exceptions, we do not recommend anyone use Outlook 2011 for Macintosh as their email client to access their MIT Exchange email and calendaring. Outlook 2011 lacks the external file features found in both Apple Mail for Mac OS and Outlook 2010 for Windows which would make recovery from a failure straightforward and easy. Instead, Outlook 2011 for Mac stores all emails and calendaring data in one massive proprietary database that cannot be recovered once the database becomes corrupted. What's worse the chances for data corruption and actual performance degradation increases with the size of the data base. It is therefore critical if you are one of the few exceptions using Outlook 2011 that you have at minimum a working Time Machine backup on your machine.
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