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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  1. Anonymous
    2016-11-23T11:59:37+00:00

    See also this thread.

    Still broken for me, same symptoms as diespie.

    The solution in that thread above worked for me - turning off auto language detection in Outlook and Word:

    In Word: 

    1. Select "Tools" -> "Language"
    2. Uncheck "Detect language automatically"

    In Outlook: 

    1. Open a new message
    2. "Edit" -> "Language" -> "Language"
    3. Uncheck "Detect language automatically"

    I suspect there is a conflict between the OS setting and where/how MS is looking for the setting.

    Useful answer was found here: https://answers.microsoft.com/en-us/msoffice/forum/msoffice\_officeinsider-mso\_mac/outlook-for-mac-1528-high-cpu-load/5ca4b1f1-e396-49b8-9aad-13467926b9b2?page=2 

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  2. Jim G 134.1K Reputation points MVP
    2016-11-23T15:21:44+00:00

    As you can see if you read through this Q&A thread Microsoft thought they had this problem fixed in an update. While they did, indeed, fix the problem for some users, it turns out there was more than one independent issue causing unusual memory use.

    Expect another fix to come down the pike eventually. It's not in the 15.29 build currently in the Fast Insider builds, but I have confidence that Microsoft is working on this problem.

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  3. Anonymous
    2016-11-28T09:47:04+00:00

    Precisely my experience! I am using Mac OS Sierra 10.12.1

    Outlook 15.28.1

    And my usage show between 48-50% when outlook is just open but idle

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  4. Anonymous
    2016-11-30T11:38:16+00:00

    Have the same problem which almost making Outlook un-usable, sometimes my macbook can spike at over 80%

    Using MacBook Pro on Mac OS Sierra 10.12.1 with Outlook 15.28.1 

    Have tried all the various suggestions on this forum and it has made no difference, it makes you think if they ever test any of this before releasing it.

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