tl;dr - If you use Outlook for Mac and you’re thinking of upgrading to OS X El Capitain, don’t…yet!
Edit (Fix): There is an update available now that fixes this problem. You can install it by opening Word, clicking ‘Help’ in the menu bar then clicking ‘Check for updates’. You should see the critical update available. Download, install it, and enjoy Outlook 2011 on your El Capitan Mac :) For more information, visit: https://support.microsoft.com/en-us/kb/3098229
It’s been an eventful day, for all the wrong reasons. Usually my Apple updates go well, but today I discovered that if you try and sync Outlook (running on El Capitan) with an Exchange server, you get a (nice, redesigned) beachball. This is a known bug (https://support.microsoft.com/en-us/kb/3098396), and the official workaround at the moment is to stick to using Yosemite.
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