High CPU usage when typing a message in Outlook

Question

OS: Win 11 Pro

Office: 2016 Pro

Hi everyone,

CPU activity goes to 16-22% when typing a message in Outlook 2016 and returns to 1 % when typing stops.

Deactivating (all) add-ins and Graphic acceleration did not solve the issue.

Deactivating spell check options did not cure the problem either.

The problem seems to be specific to Win 11 and does not occur on Win 10 OS.

If anyone has any suggestion on how to solve this issue...
PDMC

***moved from Outlook / Windows / Classic Outlook for Windows / For business***

Answer 1

And I'm sure this is part of the reason they want to "sunset" the "classic" Outlook - they don't have any good programmers who can understand this giant ball of mud anymore, but managers kept shoehorning in stupid new AI features and now it's completely screwed.

Answer 2

Dear Matth22,

thank you very much for your posting and the very detailed information, great!

At least we now know that nothing else can be done by us users, but that it's a bug that has to be resolved by Microsoft.

Answer 3

Hi all,

There are some run time operations writing an email that will affect performance. I tested on one of my VMs and these two appear to contribute a lot to the CPU. I have not tested yet if this varies between builds/versions and if this has changed any over time. If you test turning these off, restart Outlook after making each change.

1. Text Predictions, Use text predictions in Outlook for Windows - Microsoft Support. (File, Options, Mail, "Show text predictions while typing".
2. Check spelling as you type, Check spelling and grammar in Office - Microsoft Support (File, Options, Mail, Editor Options, "Check spelling as you type".

Answer 4

Gabriel,

turning off "Check spelling as you type" stopped the high CPU usage while typing issue on my system.

Thank you. I'm enjoying the peace and quiet.

Answer 5

Unfortunately, upon restart of Outlook, the CPU runs at 16% when typing, even though "Check spelling as you type", "Mark grammar errors as you type", "Frequently confused words" and "Check Grammar with spelling" are all unchecked. Tried different combos, but none worked.