What does HRESULT 0x00080012 (CO_S_NOTALLINTERFACES) mean?

CO_S_NOTALLINTERFACES

COM activation returned only some requested interfaces

CO_S_NOTALLINTERFACES is HRESULT 524306 (0x00080012) from winerror.h. The documented description is “Not all the requested interfaces were available.” The severity bit indicates a nonfailure result, but the value carries a specific condition that must not be collapsed into plain S_OK.

In the COM activation or interface negotiation, this result means that not all the requested interfaces were available. Handling is complete only after the caller verifies what work occurred and what remains outstanding.

Where the status is encountered

• COM activation requesting multiple interfaces; log the exact method and object state instead of interpreting the constant outside that contract.
• Remote COM or DCOM activation; log the exact method and object state instead of interpreting the constant outside that contract.
• Component wrappers that preserve per-interface outcomes; log the exact method and object state instead of interpreting the constant outside that contract.

What must be true before accepting it

Verify that the caller identifies exactly which interfaces were returned and whether the missing interfaces are optional for the requested feature. Failure to prove the boundary can make it look healthy while the intended operation remains unfinished.

Classify the operation phase reached when this HRESULT was returned before releasing objects or issuing replacement work.

Evidence to preserve

• Preserve CLSID and activation context.
• Preserve requested IIDs.
• Preserve per-IID HRESULT values.
• Preserve returned interface pointers and identities.
• Preserve required versus optional interface policy.

Correct handling and recovery

Inspect the per-interface results and release every returned pointer correctly. Continue only with a declared reduced feature set; fail the operation if any required interface is missing.

Difference from nearby results

S_OK would indicate that all requested interfaces were available; E_NOINTERFACE is a failure for a specific unsupported interface.

Practical scenario

A multi-interface activation asks for control, diagnostics, and optional preview interfaces. Preview is unavailable, so the application disables previews but retains the valid control and diagnostics pointers.

References

• Microsoft: IUnknown::QueryInterface — official Microsoft material relevant to this HRESULT.
• Microsoft: COM and DCOM
• Microsoft: HRESULT values