Microsoft resolves Windows 11 update installation errors

As detailed in Bleeping Computer, Microsoft has addressed a persistent issue causing installation failures and specific error codes when deploying the May 2026 Windows 11 security update, KB5089549. The problem, which surfaced two weeks prior to its acknowledgment, was linked to insufficient free space on the EFI System Partition (ESP).

The installation failures, often accompanied by messages like "Something didn't go as planned. Undoing changes," and log entries indicating "SpaceCheck" and "ServicingBootFiles failed," occurred when the ESP had 10 MB or less of available space. This led to the update automatically rolling back during the reboot phase.

Microsoft has resolved this by releasing the KB5089573 preview cumulative update, with the fix slated for inclusion in the June Patch Tuesday updates. For those not yet updated, Microsoft's Known Issue Rollback feature or manual Group Policy configuration can be used as workarounds.

Source: Bleeping Computer