Disabling Windows telemetry: AllowTelemetry, DiagTrack, and what actually stops
SHORT ANSWER
Setting AllowTelemetry to 0 under SOFTWARE\Policies\Microsoft\Windows\DataCollection and disabling the DiagTrack service stops the Connected User Experiences and Telemetry service collecting and uploading diagnostic data. The privacy benefit is real. The performance benefit is small — this is a privacy tweak that gets marketed as an FPS tweak.
Exactly what it changes
Read straight from the application source. If a tool will not show you this, it is asking for trust it has not earned.
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\DataCollection
AllowTelemetry = 0
Policy setting requesting the lowest telemetry level.
DiagTrack — Connected User Experiences and Telemetry
Disabled so it no longer runs or uploads.
What it does
DiagTrack batches diagnostic and usage data and uploads it periodically. It is not continuously heavy, which is why the FPS claims around it are overstated.
On Windows Home the AllowTelemetry policy is honoured less completely than on Pro and Enterprise. Disabling the service is the part that reliably takes effect.
When it helps
- A genuine reduction in what leaves your machine.
- Removes periodic background disk and network activity, which occasionally coincides with a hitch.
When it hurts
- Windows Feedback and some diagnostic tooling stop working properly.
- Certain Windows Update troubleshooting paths rely on this data being present.
- The frame-rate improvement is close to unmeasurable on any modern system. Treat this as privacy, not performance.
How to undo it
Delete the AllowTelemetry value and set DiagTrack back to Automatic. Frozen Tweaks restores the original service start type.
Verdict
Do it for privacy reasons if you want to. Do not expect frames, and be sceptical of anyone selling it as a performance tweak.
Related guides
Everything else we change is listed too
All 127 optimizations are published in full, with what each one does and which are free. You can apply any of them by hand using pages like this one — the tool exists to do it in one click and put it back after every Windows update.