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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.
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.
Holy cow, I have been searching a fix since 15.10! who will think it's the flags!
In my case, I was importing from my windows pst into osx, and outlook has been eating my energy since then, deleting profile, reinstall, non of them fix it after i importing the pst again. After taken out all the old email red flags, now it's back to normal. Thanks KeithSWD for tracking the 'bug' down!
My Hotmail account which has always served me well was arbitrarily changed to Outlook by Microsoft. When I run Outlook my computer is literally disabled. My Cpu runs at maximum and it is impossible for m to use my computer. What I find amazing is that this is a Microsoft page and yet I have seen nothing from Microsoft addressing this issue. This is not a new issue. Microsoft seems to be incapable or unwilling to resolve this problem. Give me back my Hotmail or fix the problem. Gmail, here I come.