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 recognized difficulty is brought on by inadequate free house on the EFI System Partition (ESP), which ends up in the replace routinely rolling again on affected gadgets.
“This difficulty impacts gadgets with restricted free house on the EFI System Partition (ESP), particularly when the system has 10 MB or much less house obtainable,” Microsoft said.
“On affected gadgets, the set up may proceed by means of the preliminary phases however fail throughout the reboot section 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 should discover log entries pointing to inadequate ESP free house, resembling:
- “SpaceCheck: Inadequate free house”
- “ServicingBootFiles failed. Error = 0x70”
- “SpaceCheck:
utilized by third-party/OEM information outdoors of Microsoft boot directories”
Whereas Microsoft remains to be working to resolve this difficulty, it suggested affected clients to mitigate it utilizing the Known Issue Rollback (a Home windows function 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 Policy.
“You’ll need to put in and configure the Group Coverage in your model of Home windows to resolve this difficulty,” Microsoft mentioned. “Additionally, you will must restart your system(s) to use the group coverage setting. Word that the Group Coverage will briefly disable the change inflicting this difficulty.”
Yow will discover additional steerage on deploying and configuring Identified Concern Rollback group insurance policies on Microsoft’s support website.
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 recognized difficulty that causes some Home windows 11 techniques besides 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 prompted 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 susceptible driver.
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