What does HRESULT 0x80004034 (CO_E_UNREVOKED_REGISTRATION_ON_APARTMENT_SHUTDOWN) mean?

CO_E_UNREVOKED_REGISTRATION_ON_APARTMENT_SHUTDOWN

Apartment shut down with a COM registration still active

CO_E_UNREVOKED_REGISTRATION_ON_APARTMENT_SHUTDOWN is HRESULT 2147500084 (0x80004034) from winerror.h. The documented description is “The caller failed to revoke a per-apartment registration before apartment shutdown.” The value must be interpreted at per-apartment class, callback, or interface registration tied to apartment lifetime.

The apartment began shutdown before the owner revoked a registration that must not outlive it.

Where the result appears

• This result may surface in per-apartment class, callback, or interface registration tied to apartment lifetime.

Typical causes and interpretation

Common cause categories are: cleanup was skipped on an exception; ownership moved across threads; the apartment exits while callbacks remain registered. The evidence should distinguish configuration, lifetime, input, identity, resource, and version failures rather than grouping them.

Key distinction: the apartment began shutdown before the owner revoked a registration that must not outlive it.

Correct handling and recovery

The appropriate recovery is to store the registration cookie with apartment-owned state, revoke it before CoUninitialize, stop callbacks first, and make teardown idempotent.

Practical scenario

A UI extension registers a per-apartment handler but closes the window without revoking it; teardown is updated to revoke before apartment shutdown.

Difference from related HRESULTs

CO_E_PREMATURE_STUB_RUNDOWN concerns remote object lifetime after clients exist; this code concerns a registration left active by its owner.

References

• Microsoft: COM security defaults
• Microsoft: HRESULT values
• Microsoft: COM error codes