In my office environment, cable or wi fi, the problem does not exist. It only does this when i connect my macbook pro to a different network. ie a Telstra 4G wi fi dongle(this is how i found this issue to begin with), or my home ADSL wifi does the same.  As soon as Outlook connects, it goes into freakout mode like it is trying to download and upload all known information to man.. there are 2 other mac users in my office, all configured the same(well we think) but only my machine has this issue..Our mail servers have quite small size limits (10 meg or something) so i dont think it is that.

I installed little snitch to find out what app was responsible and its defiantly outlook, nothing trying to send etc etc outlook looks idle, its only the little snitch meters and log that show outlook is maxing out the available bandwidth.. put 36 gig on the 4G dongle in about 9 hours! Telstra kindly waived the $500 charge for going over the limit..on the condition if it happens again we pay.. how nice of them. I imagine Telstra and other ISP's are huge supporters of this problem..  HELP PLEASE....  ANYONE>>> I have come across a few other threads where people have this problem, but no solution..