Microsoft finally shares workarounds for Windows 11 bug that breaks Outlook in many ways

Microsoft has finally issued workarounds for Outlook bugs that apparently made the application "completely unusable" after the latest Windows 11 update.

outlook on top of windows 11 bloom in red indicating bug or issue

Last week, Microsoft released the first Patch Tuesday updates of 2026 on Windows 11 under KB5074109 and KB5073455. Alongside that, the company also published related dynamic updates under KB5074108, KB5074208, and KB5073454.

Unfortunately for users, the Patch Tuesday update has some major issues, and as such, Microsoft was forced to release emergency OOB updates for them to patch those issues under KB5077744 and KB5077797.

However, the first Patch of 2026 on Windows 11 25H2, 24H2 (KB5074109) has continued to be notorious, as it has led to issues on classic Outlook too, which apparently made the app "completely unusable" for certain users. Microsoft initially did not release a workaround for the feature but has since updated its documentation.

While the unofficial workaround was to uninstall the Windows update leading to the issue, the company has now added some more details regarding the issue, including workarounds, after further investigation.

The company has explained in the updated support document: "After Windows updates on January 13, 2026 users with Outlook POP account profiles and profiles with PST files report that Outlook hangs and does not exit properly. This issue may occur for any Outlook profile that has PSTs stored on OneDrive. Symptoms reported include:

Outlook hangs and shows “Not Responding”.
Inability to reopen Outlook without ending its process in Task Manager or restarting the computer.
Emails not appearing in the Sent Items folder despite being sent.
Outlook redownloading emails."

While the tech giant has confirmed that it continues to investigate the problem, it has offered workarounds for admins and users alike who are affected by this issue. These include using the webmail, moving PSTs out of OneDrive, and last but not the least, uninstalling the KB5074109 Windows update. It says:

"Until a fix is available, please use webmail. The other workarounds may be complicated.

Use webmail.
Move PSTs out of OneDrive.
Remove the Windows Update."

You can find the support article here on Microsoft's official website. Aside from these confirmed issues, users have also reported GPU-related bugs too.