What does HRESULT 0xC0380038 (ERROR_VOLMGR_PLEX_IN_SYNC) mean?

ERROR_VOLMGR_PLEX_IN_SYNC

Interpret the state transition: volmgr plex in sync

Windows returns ERROR_VOLMGR_PLEX_IN_SYNC, value 0xC0380038, at the volmgr boundary. It means that the selected volume plex already represents the same committed data as the other active plexes. Preserve the exact handle and generation of volume plex descriptor, layout type and regeneration state before any rescan changes the evidence.

Record geometry, identity and ownership

Do not overwrite this result with a close, detach or rollback error. Preserve the causal order so the original storage contract remains visible.

Separate validation from capability

1. serialize the failing request and the enumeration from which its identifiers came.
2. Preserve volume ID, plex ordinal, plex type, member array, active/inactive state, health status and current regeneration job while every handle is still valid.
3. Repeat the operation using this controlled change: query health and synchronization state before requesting regeneration, then compare with a deliberately stale test member or plex.
4. Close and reacquire the relevant objects, then run once more to test lifecycle correctness after it.

A useful diagnostic fork is ERROR_VOLMGR_PLEX_REGENERATING versus it. This code concerns the selected volume plex already represents the same committed data as the other active plexes; the alternate code should remain observable after the fix, proving the application did not suppress the entire subsystem.

Mechanism-specific note

This is an idempotency boundary. The object is healthy enough that another regeneration request would add work without changing redundancy. Verify the reported synchronization generation and health of the other copies; if data is still suspected, investigate checksums or the actual stale object rather than forcing a rebuild of the already synchronized one.

Verification after correction

Treat the result as state feedback and skip regeneration for that object; refresh health information before deciding whether another member or plex needs repair. Keep the correction scoped to the owning object and avoid rewriting adjacent metadata merely to make the call return success.

• The controlled A/B case changes only the invariant that triggers this result.
• No unrelated disk, cluster owner, tier policy or virtual-disk backing file is altered to hide it.
• Health, synchronization or job state reaches a terminal value consistent with the repaired operation.
• Telemetry includes both symbolic names when it or ERROR_VOLMGR_PLEX_REGENERATING occurs again.

Technical references

• Microsoft: COM error codes for VOLMGR, VHD and SDIAG — primary API or object-model reference.
• Microsoft: Virtual Disk Service object model — use this source to verify volmgr state and parameters.
• Microsoft: Pack object — documents the supported management path relevant to this HRESULT.
• Microsoft: Virtual Disk Service common return codes — defines the volmgr objects used to interpret it.