Microsoft confirmed that the KB5074109 January Windows 11 security update causes the classic Outlook desktop client to freeze ...

If your Outlook Classic freezes or hangs when you use POP accounts or deal with PST files, you'll need to remove Windows 11 ...

At last there’s a fix. Millions of Outlook users been plagued with failed restarts and missing emails since Microsoft ...

Windows 11 KB5078127 is an 'out-of-band' patch to fix an issue that broke Outlook Classic (POP, PST) after January 2026 Patch ...

There are workarounds, though.

Microsoft admits that “Classic Outlook profiles with POP accounts and PSTs hang after Windows updates on January 13, 2026.” If you’re affected, you need to await a fix. “The Windows Team will be ...

Windows 11 KB5074109 causes Outlook freezing for POP accounts. Microsoft confirms the issue and investigates a permanent fix.

Microsoft shared a temporary workaround for customers experiencing Outlook freezes after installing this month's Windows ...

Microsoft shares workarounds for a Windows 11 KB5074109 bug that breaks Outlook for POP email accounts and PST files.

Microsoft's January security updates for Windows 11 also appear to be disrupting Outlook. Microsoft is investigating problems ...