What does HRESULT 0x87C5100A (UTC_E_DIAGRULES_SCHEMAVERSION_MISMATCH) mean?

UTC_E_DIAGRULES_SCHEMAVERSION_MISMATCH

Identify the owning component: diagnostic-rules document version

When UTC_E_DIAGRULES_SCHEMAVERSION_MISMATCH (0x87C5100A) is returned, the producing layer is DiagTrack scenario-definition processing. Correlate this HRESULT with the exact request attempt that returned it. The rejected object or state is diagnostic-rules document version, and the specific condition is that the diagrules document declares a schema version outside the range supported by this UTC client. Keep this first HRESULT even if a later service call reports another error.

DiagTrack scenarios are configuration-driven state machines. A scenario definition, its diagnostic rules, referenced profiles, triggers and action graph must all come from a compatible configuration generation. Mixing authoring files or package versions can make an otherwise valid identifier unusable.

What to capture before retrying

Prove the condition

1. Export the relevant Microsoft-Windows-UniversalTelemetryClient/Operational events and preserve their ActivityId or request correlation alongside this result.
2. Capture diagrules schemaversion, client build, package provenance, signing information and load event. Do this before restarting the service or deleting any working directory.
3. Perform this one-variable comparison: load a rules file generated for the target build while keeping the scenario and triggers constant.
4. After the comparison, record the next HRESULT and whether the requested session, action, trigger or output object was actually created.

Nearby result: UTC_E_SCENARIODEF_SCHEMAVERSION_MISMATCH — applies to the scenario document rather than diagrules.

Configuration-generation check

Hash the scenario, rules and referenced profile files used and record the UTC process start time. If files changed after the process loaded them, restart only after preserving the prior generation so the comparison remains auditable.

Confirm the repair

Ship the rules package that matches the installed client or transform it with the supported authoring tool.

Technical references

• Microsoft Open Specifications: Windows error-code registry — reference for DiagTrack scenario-definition processing while interpreting this result.
• Microsoft: Universal Telemetry Client configuration diagnosis — reference for DiagTrack scenario-definition processing while interpreting this result.
• Microsoft: UniversalTelemetryClient operational-log guidance — reference for DiagTrack scenario-definition processing while interpreting it.
• Microsoft: Windows Event Log query schema