Outlook 2016 CPU usage running continuously at around 100%

Anonymous
2015-07-29T05:38:02+00:00

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.

Outlook | MacOS | Legacy Outlook for Mac | For business

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Anonymous
2017-03-14T12:50:52+00:00

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.

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46 additional answers

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  1. Anonymous
    2016-11-07T14:19:04+00:00

    removing the flags on older emails did the trick for me...

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  2. Anonymous
    2016-07-19T23:13:29+00:00

    I have applied this fix and did not help.  Outlook sky rockets over 100% switching between email and calendaring and sometimes when just sitting idle.  

    In response to the Flagged Messages that seems to be working for everyone.  Are you removing the flags from the messages or completely removing the emails altogether?

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  3. Anonymous
    2016-06-15T23:24:43+00:00

    Hi everyone,

    This issue is now fixed. For more information about how to obtain the fix, see https://support.microsoft.com/en-us/kb/3165798.

    We very much appreciate your patience!

    Best,

    -Erik

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  4. Anonymous
    2016-06-03T22:10:29+00:00

    Hi all,

    The "Insiders Fast" public update (which has other bug fixes and new features, as well) that has just been release will fix one specific high-CPU scenario (but nothing with flags).  Go to "Help"->"Check for Updates" and opt in to the "Insiders Fast" program at the bottom to get the new update.  If you are on "Insiders Slow" or have not opted into a pre-release, then you will have to wait a few more days for the update.

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