High CPU usage when typing a message in Outlook

OK, I will check and report about the GPU bug again later after the CPU bug will be fixed.

How long should it take until the CPU bug, which you mentioned now to occur also in SemiAnnual Enterprise Channel, will also be fixed in SemiAnnual? So would it be an alternative to disable updates using SemiAnnual Channel in time before the latest update (which should bring the CPU bug also to SemiAnnual), because here at my side I don't have it in SemiAnnual Channel up to now and I'd prefer to wait maybe 6-8 weeks until it will also be fixed in SemiAnnual?

Because after this "special" experience with the CPU bug which was not fixed for such a long time over many months, I would generally prefer to stay in SemiAnnual Enterprise Channel for the future.

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 Gabriel,

thank you very much, so I will re-enable updates for SemiAnnual Channel.

I can see the GPU spike when I switch from mailbox to calendar in classic Outlook - then suddenly GPU load rises to and stays between 30-60%, and it does not drop afterwards, but stays high until I quit and restart Outlook. But this happens not every time, only quite often. My graphics driver is up to date.

Dear Gabriel,

the GPU (not CPU) bug happens too often now: I cannot restart Outlook 5-10 times times every day to stop the GPU from running perpetually, so that I preferred to do the rollback to 2405 again instead of SemiAnnual Channel. My productivity went down too much checking and taking care all the time of this bug.

2405 reacts really very much quicker than the later versions incl. SemiAnnual Channel 2408 which have been slowed down extremely: When you switch from mailbox to calendar or from inbox to sent mails, for example, it takes nearly a few seconds for each click (and sometimes the GPU starts running with high load without any end [Task DWM.exe in Task Manager], until you quit Outlook - or put other windows over Outlook, but as soon as Outlook is on top again, the CPU load continues), whereas 2405 reacts on the spot without delay.

This seems to be a separate bug, because even SemiAnnual Channel, which has not the CPU bug, is concerned by the GPU bug.