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I recently purchased a Office 365 Business plan, and have installed the desktop Office 2016 apps. I am experiencing continuous high CPU utilization, causing the fan in my MacBook to run much of the time. Activity Monitor shows that Outlook is the culprit.
I have Outlook 15.11.2 and OS X 10.10. I have one Exchange 2010 (SP2) accounts and two IMAP accounts. All are showing folders up to date, and mail is being sent & received normally.
I haven't noticed any issues with the other Office 2016 applications.
I have already tried creating a new identity and setting up accounts again from there (rather than importing from OUtlook 2011 which I did at first installation), but it did not help.
I have also installed the suite on my iMac, and experience the same issue there, so it is not specific to my laptop.
There is an earlier thread on this issue, started in 2014 and with posts up to mid July this year, with not a single response from MSFT. It is clear there is a bug here, as it stands I am going to have to abandon Outlook 2016 and revert to 2011, so if it can't be fixed I'd like a refund.
Using older versions of Outlook for Mac in business environments
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
I tried every option listed in this thread - to no avail.
What worked for me was to turn off Dictation: (System Preferences\Accessibility\Dictation)
As soon as I did that, the CPU use returned to normal instantly.
Thanks RobertLed,
I was having problems with this too (CPU around 50% to 60% on outlook 2016, 32bit) and this solution did the trick.
To help others I'm running windows 10 on a macbook pro retina and email is via google app using google apps sync.
After i deleted the old task flags (have not used flags in years anyway) it took about 10 mins for it to settle and now outlook is using zero CPU and has been for 3 hours while I'm still sending and receiving emails!
I finally found out the reason for my high cpu problem (constantly at 130% and higher) when using Outlook for Mac 2016. It was my Follow Up flagged messages dating back to 2010. I removed all of them.
Now my Outlook's cpu hovers at near 0% levels.
Thanks a lot. This fixed the issue for me instantly. I am using outlook 2013 and windows 8.
Kaspersky Total Security was the cause of this issue for me.
As well as another issue where Outlook would complain the message had changed whenever I tried to move it to another folder.
Do you remember whether you had reminders for all those old flagged messages? Do you ever use the "Task" view or the Flagged Mail smart folder? We're trying to understand when and why this is causing a performance issue.