Microsoft has confirmed that the Could 2026 Home windows 11 safety replace (KB5089549) fails to put in on some techniques and triggers 0x800f0922 errors.
This identified situation is brought on by inadequate free area on the EFI System Partition (ESP), which ends up in the replace mechanically rolling again on affected gadgets.
“This situation impacts gadgets with restricted free area on the EFI System Partition (ESP), particularly when the gadget has 10 MB or much less area obtainable,” Microsoft stated.
“On affected gadgets, the set up may proceed by way of the preliminary phases however fail throughout the reboot part at roughly 35–36% completion.”
Customers impacted by these set up issues additionally see the “One thing did not go as deliberate. Undoing adjustments.” message when the set up rolls again, and will discover log entries pointing to inadequate ESP free area, corresponding to:
- “SpaceCheck: Inadequate free area”
- “ServicingBootFiles failed. Error = 0x70”
- “SpaceCheck:
utilized by third-party/OEM recordsdata exterior of Microsoft boot directories”
Whereas Microsoft remains to be working to resolve this situation, it suggested affected clients to mitigate it utilizing the Identified Concern Rollback (a Home windows characteristic that reverses buggy updates pushed by way of Home windows Replace).
In enterprise-managed environments the place IT departments management Home windows updates, admins can manually mitigate it by putting in and configuring this Group Coverage.
“You have to to put in and configure the Group Coverage on your model of Home windows to resolve this situation,” Microsoft stated. “Additionally, you will must restart your gadget(s) to use the group coverage setting. Observe that the Group Coverage will quickly disable the change inflicting this situation.”
You could find additional steerage on deploying and configuring Identified Concern Rollback group insurance policies on Microsoft’s assist web site.
Microsoft launched the KB5089549 cumulative replace final week, together with dozens of different bug fixes, safety patches, and enhancements, together with a repair for one more identified situation that causes some Home windows 11 techniques as well into BitLocker restoration after putting in the April 2026 Home windows safety updates.
Earlier this month, Microsoft additionally addressed a Home windows Autopatch bug that triggered driver updates restricted by administrative insurance policies to be deployed on some Autopatch-managed Home windows gadgets throughout the European Union, and confirmed that the April 2026 safety updates have been inflicting failures in third-party backup functions utilizing a weak driver.
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