Microsoft has pushed out another emergency update for Windows 11 after its latest monthly patch caused unexpected app crashes and system issues for users. What was meant to be a routine January security update quickly turned into a problem, with reports piling up about apps freezing, Outlook breaking, and cloud-synced files refusing to behave.
Some of the problems were serious enough that Microsoft even advised certain users to uninstall the update altogether. Now, Microsoft has stepped in again with a second out-of-band update, aiming to finally steady the ship.
Why Microsoft had to step in again
The trouble began with the January Patch Tuesday update, which introduced bugs that affected how apps interacted with files stored in cloud services such as OneDrive. Soon after installing it, some users found that everyday apps became unstable.
Outlook was one of the worst hit, especially for people using classic Outlook with PST files saved in OneDrive folders. In many cases, Outlook would freeze, crash on launch, or repeatedly download old emails, making it nearly unusable.
Microsoft initially released an emergency fix earlier in the month to address problems like shutdown errors and Remote Desktop issues. However, that first emergency update did not fully solve the app-crashing problem and, in some cases, added new complications. This led to the release of a second emergency cumulative update, marked as KB5078127.
The new update combines earlier security fixes with targeted repairs for the app crashes tied to cloud-stored files. It specifically addresses the Outlook PST issue and broader problems where apps stopped responding when opening or saving files in synced folders. For users who rely on cloud backups for work or personal data, this fix is especially important.
KB5078127 is now rolling out through Windows Update for supported Windows 11 versions. It installs automatically for most users, but it can also be checked manually. Even if you did not notice crashes, installing it is still recommended since it includes security and stability improvements from earlier updates.