Microsoft admits it's not you, Classic Outlook can be a real CPU, power hog sometimes

Bug or migration strategy for New Outlook, we wonder

Far be it from us to suggest Microsoft is trying to force people onto its New Outlook application, but it has admitted Classic Outlook occasionally and mysteriously turns into a system resource hog.

It's a SNAFU that may just push folks over the edge to the new app – or to a full alternative.

The Windows behemoth earlier this week confirmed its software goes awry, and said users may experience CPU usage spikes of up to 30 to 50 percent and increased power consumption.

Users flagged the issue as far back as November 2024, and Microsoft has finally acknowledged that something odd is going on. Affected customers say it happens on Windows 10 and 11.

The issue can be observed by opening Task Manager and watching the CPU usage rise. Microsoft offered little in the way of a fix, saying only that "the Outlook Team is investigating this issue."

It did provide a workaround to force a switch to the Semi-Annual Channel update, where the problem has not appeared. However, the workaround involves fiddling with the registry (as administrator), which most enterprises are unlikely to welcome.

The classic version of Outlook doesn't have much time left, though Microsoft has yet to set a definitive end date. The IT titan is eager for users to move to its new client, even if it still lacks some features. The conspiracy-minded among us may argue triggering high CPU usage in the legacy app is a forced-upgrade tactic, however heavy handed. Does Redmond have it in it to intentionally hobble an older product just to steer users toward something newer and flashier?

As another workaround, users have suggested writing emails somewhere else and then pasting them into Outlook to send. However, with the amount of AI functionality in Notepad these days, an email to Microsoft support will likely require a surprising amount of power just to type: Dear Satya, Pls stop breaking my system. Thx. ®