What does Windows error code 4550 (ERROR_SYSTEM_INTEGRITY_ROLLBACK_DETECTED) mean?

ERROR_SYSTEM_INTEGRITY_ROLLBACK_DETECTED

System Integrity detected that policy rollback has been attempted.

ERROR_SYSTEM_INTEGRITY_ROLLBACK_DETECTED is Win32 error 4550 (0x11C6) and belongs to System Integrity policy anti-rollback.

Where the result appears

• Loading or applying a Windows code-integrity policy.
• Device Guard or WDAC servicing.
• Boot-time validation of an updated policy.
• Enterprise deployment that replaces an existing policy.

Likely causes

• the proposed policy has an older version or rollback counter.
• deployment restored a stale policy from backup.
• firmware or protected state records a newer authorized policy.
• multiple management systems published policies out of order.

Troubleshooting steps

• Record current and proposed policy IDs and versions.
• Record signer and signature chain.
• Record deployment source and timestamp.
• Record CodeIntegrity operational events.
• Record boot and servicing history.

What to verify

Verify whether the proposed policy has an older version or rollback counter. Check current and proposed policy IDs and versions together with signer and signature chain.

Handling, retry, and recovery

Do not bypass anti-rollback protection. Deploy a correctly versioned authorized policy through the supported management channel and verify the active policy after restart.

Difference from nearby codes

INVALID_POLICY means the policy structure or semantics are unacceptable; ROLLBACK_DETECTED specifically protects against moving to an older policy state.

Practical example

A disaster-recovery image contains last month’s WDAC policy while protected state records a newer revision.

References

• Microsoft: System Error Codes (4000–5999) — reference for error 4550.
• Microsoft: Windows Defender Application Control — reference for error 4550.
• Microsoft: Application Control event logs — reference for error 4550.