High CPU usage when typing a message in Outlook

Hi all,

The fix for the CPU spike when typing is now at Current Channel and Monthly Enterprise Channel with the May Patch Tuesday update. The build is not pushed yet so to install it click File, Office Account, Update Options, Update Now.

I updated the Known Issue article with the updated fixed builds from the backports, CPU spikes when typing in classic Outlook for Windows - Microsoft Support.

I did some more follow up for Semi Annual Channel. It turns out after all that the change that causes the CPU spike is not at that channel. My tests are not exactly perfect because my VMs are very resource constricted. Comparing SAC to Current Channel I see a huge noticeable difference. Regular typing does not spike SAC for me like it does on CC or MEC. If you are on SAC you can stay there to avoid seeing this bug again.

I also tested my VMs for the GPU spike you mentioned and so far, I cannot cause that issue. If you are doing anything unique where you see that spike please let me know so I can test further. The main thing to check there is that you have the latest graphics drivers. I will keep monitoring though to see if there are other reports with GPU.

Since SAC does not have the bug I am updating the Known Issue again to suggest it as the best workaround for now, CPU spikes when typing in classic Outlook for Windows - Microsoft Support.

Dear Pascal,

I use Microsoft 365 with current channel. That's Office with at least monthly updates, so you always get the latest version (as soon as they are officially released, so no previews): https://learn.microsoft.com/de-de/officeupdates/update-history-microsoft365-apps-by-date?redirectSourcePath=%252fen-us%252farticle%252fae942449-1fca-4484-898b-a933ea23def7

So my Outlook is version 2411, Build 18227.20046. It also has this bug. So if you update your Office, it will most probably not solve this problem, unfortunately.

Here is a (dumb) solution to somehow circumvent the problem: I type the mail into Notepad (Window 11 Notepad has a spellcheck) as a buffer, and then paste the resulting text into Outlook. This way the processor does not go red hot as you type into Outlook.

Another solution is to use Word 2K16 to type your message. Surprisingly Word does not exhibit this high CPU usage problem as you type.

Yet, Outlook uses Word engine in its editing mode....

Dear PASCAL DMCHRETIEN

Thank you for posting to Microsoft Community

Based on your description, I understand that you are experiencing high CPU usage while typing emails in Outlook 2016.

I understand your frustration, but the issue has not been successfully resolved in Outlook 2016 even though you have troubleshot add-ons, graphics acceleration, and deactivated spell checking options, and the issue is primarily occurring on Windows 11, so I would recommend that you contact Microsoft Online Support directly, where you can communicate with them about the issue you are experiencing via chat, and ask them to remotely, if necessary!  Chat specialists will answer your questions immediately. The chat window is one-on-one and the chat specialists will answer your questions immediately and deal with them more efficiently! 

you can click on the link below to log into your personal Microsoft account and chat directly with chat support.

1. Open this link Contact Us - Microsoft Support

2. Select Office. At the bottom of the page. Select the Contact Support option.

3. Select Microsoft 365 and Office.
4. In Categories, you can select Technical Support  and confirm it.

5. Then select Chat with a support agent in a web browser.

TIPS: Please contact us during local working hours on weekdays, CHAT does not work 24 hours a day.

Wish you all the best and have a nice day!

Linda.W-MSFT | Microsoft Community Support Specialist