High CPU usage when typing a message in Outlook

Dear Wage Slave,

Thank you for your feedback confirming that this problem is not an isolated case, although being ignored by Microsoft (just like many other pending issues).

As previously mentioned, the only temporary fix might be to redact the mail in Notepad, and then paste it into Outlook before sending (other solution: get rid of all Microsoft products, including their OS).

Best regards.

Just to note i'm running 2411 build. So this doesn't appear to be unique to the older versions.

Dear Pascal,

the problem is often with customer service departments, that they do not take problems seriously if not at least hundreds of users complain. The point with this bug is that Outlook does not crash, what everybody would notice, but that "just" the CPU is running hot again and again. Many PCs have fans that run very often or permanently also without this bug, so that users hear no big difference. And they will also not check it in task manager. Moreover, the misbehavior does not slow down Outlook so much that you feel it because current CPUs are still powerful enough to enable fluent working even with one CPU core on 100% load. So a friend of mine has the same bug using Windows 11, but she wouldn't have noticed it if I didn't ask her. That's why only a few people like us will notice it, who have silent PCs whose fans normally do not run whily typing e-mails, but now they do.

As I mentioned, I tried some rollbacks to former versions of Office/Outlook (2409, 2408 and 2406), but that didn't help. So I suppose that something else has changed 2 months ago, maybe Windows Defender or something else within Windows, what makes Outlook cause this trouble now. But that's just a supposition.

Dear Dark Rider,
Thank you for this valuable info. You have a good point, here.
But then, why aren't more people complaining about the problem ?
I just can't make it. It is no longer some lunatic like me still using Office 2K16, but the whole 365 community, right ?
Besides, the problem is less than two month old; It was introduced by an update ; so it should not be that difficult for Microsoft to trace it and solve it.
Someone must have fallen asleep behind the wheel. What is Microsoft doing appart sticking their head in the sand ?

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.