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Windows 11 KB5089549 security update installation failures due to EFI System Partition space constraints

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1 unique sources, 1 articles

Summary

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Microsoft confirmed that the May 2026 Windows 11 security update KB5089549 fails to install on systems with insufficient free space on the EFI System Partition (ESP), triggering automatic rollback and error code 0x800f0922. Affected devices—particularly those with 10 MB or less free space on the ESP—progress to approximately 35–36% completion before failing, displaying the message "Something didn't go as planned. Undoing changes." The issue stems from third-party or OEM files occupying space outside Microsoft boot directories, as indicated by log entries such as "SpaceCheck: Insufficient free space" and "ServicingBootFiles failed. Error = 0x70".

Timeline

  1. 18.05.2026 11:33 1 articles · 19h ago

    Windows 11 KB5089549 installation failures due to EFI System Partition space constraints

    Microsoft confirmed that KB5089549 fails to install on systems with insufficient free space on the EFI System Partition, triggering automatic rollback at ~35–36% completion with error code 0x800f0922. Mitigation options include Known Issue Rollback (KIR) and Group Policy configuration to temporarily disable the problematic update component.

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Information Snippets

  • The Windows 11 security update KB5089549 fails to install on systems where the EFI System Partition (ESP) has 10 MB or less free space, causing automatic rollback during the reboot phase at approximately 35–36% completion.

    First reported: 18.05.2026 11:33
    1 source, 1 article
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  • Installation failures generate error code 0x800f0922 and display the message "Something didn't go as planned. Undoing changes." when the update rolls back.

    First reported: 18.05.2026 11:33
    1 source, 1 article
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  • Log entries indicate the failure is linked to insufficient free space on the ESP, often due to third-party or OEM files outside Microsoft boot directories. Specific log entries include "SpaceCheck: Insufficient free space", "ServicingBootFiles failed. Error = 0x70", and "SpaceCheck: <value> used by third-party/OEM files".

    First reported: 18.05.2026 11:33
    1 source, 1 article
    Show sources