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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.
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.
It appears that I have at last resolved this problem, albeit without discovering the root cause:
I found that even after creating a new 'empty' Main Profile with no email accounts configured, Outlook was still running the cpu at 100%. To do this, quit Outlook and use Profile Manager, which has to be revealed by right-clicking Outlook in the Applications folder, selecting Show Package Contents, then navigating to Contents/Shared Support. You can then create a new profile (any name, like TEST) and set it default. Start Outlook but do not import any data or configure any mail accounts. Check your CPU usage.
Having established that the issue was not related to my mail accounts, I then located my original Main Profile (in ~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles) and moved it to my Desktop.
I then did a complete uninstall of Office 2016, using this method: Completely uninstall Office 2016
Office was then reinstalled, after downloading the current installation package.
After rebooting and starting Word initially to verify license etc. I moved my Main Profile folder back to its original location and started Outlook.
Everything appears now to be working normally.
Still no fix for this issue, and very frustrating that I have paid for a product that I cannot use and there appears to be no way of getting tech support, other than paying $500 for an incident. (If anyone knows another way to contact MSFT please let me know.)
I am forced now to either abandon Outlook 2016 and use either web access or roll back to Outlook 2011.
I can confirm that updated to version 15.12.3 did not fix the issue.
Nor did a reboot. I also tried removing the exchange account from my profile, restarting and adding it back again.
The high CPU usage persists.