# CompatTelRunner.exe

Windows Process: Microsoft Corporation

Also called compattelrunner, compatibility telemetry, microsoft compatibility telemetry

Windows, System Component

Compatibility Telemetry runner. Scheduled tasks start it to collect compatibility data Microsoft uses for upgrades and problem reports.

## What you need to know

This is Compatibility Telemetry, a scheduled Microsoft task. It is not Defender and it is not a browser.

CompatTelRunner.exe runs Microsoft Compatibility Telemetry. High disk for a while after an upgrade is common. Disabling the scheduled task is the supported control, not deleting System32.

- **Safe?**: Yes, in System32

  **High disk?**: A compat scan can do that

  **Can I disable it?**: Through the task, not by deleting the file

Feex says

If CompatTelRunner is the disk hog after a feature update, I would let the task finish once. I would not rename the exe. That is how servicing repairs start failing.

## What is CompatTelRunner.exe?

CompatTelRunner.exe is the host for Microsoft Compatibility Telemetry. Task Scheduler launches it from Microsoft / Windows / Application Experience.

## What does it do?

It inventories apps and drivers that might break on a newer Windows. It is not CompatTelRunner collecting passwords. It is not SearchIndexer.exe.

## Why is it running?

A daily or idle trigger fired, or you just installed a feature update. A runner that never exits for days is stuck and worth a task restart.

## Is it safe?

Usually safe

System32 CompatTelRunner is Microsoft. The same filename in a "disable telemetry" zip is not.

A legitimate copy normally runs from:

`C:\Windows\System32\CompatTelRunner.exe`

- Started by Application Experience tasks
- Not Windows Search
- Not Defender

## Can I end it?

Stops this run

Ending CompatTelRunner.exe stops the current inventory. The task will start again on the next trigger unless you disable that task.

## Can I remove it?

No

Do not delete CompatTelRunner.exe. Disable Microsoft Compatibility Appraiser in Task Scheduler if you accept less upgrade-readiness data.

## Should it start with Windows?

A scheduled task starts it. It should not be a Startup Apps row.

## Normal resource behavior

These are contextual labels, not universal averages.

- **CPU**: Can rise while inventorying

  **Disk**: The usual complaint on HDD

  **Network**: If diagnostic sending is allowed

  **Memory**: Moderate

## File information

| Executable name        | CompatTelRunner.exe                     |
| ---------------------- | --------------------------------------- |
| Common legitimate path | C:\Windows\System32\CompatTelRunner.exe |
| Publisher              | Microsoft Corporation                   |
| Signature expectation  | Signed by Microsoft Windows             |

## Common problems

### 100 percent disk for an hour

On a spinning disk the Appraiser is slow. Wait, then check Task Scheduler history. SearchIndexer is a different row if the disk stays busy.

### Scripts that take ownership of the file

Those break servicing. Use the task, not ACLs.

## Troubleshooting

Diagnose before you change anything destructive.

### Task Scheduler > Application Experience

Microsoft Compatibility Appraiser is the usual name.

### Do not replace the runner

Windows Update will fight you.

## Technical details

Technical details

| Image name | CompatTelRunner.exe            |
| ---------- | ------------------------------ |
| Role       | Compatibility Telemetry runner |

## Related

These entities connect to this article. Type is shown on every link.

[taskhostw.exe: Windows Process](https://feex.it/wiki/process/taskhostw.exe)[Task Scheduler: Windows Service](https://feex.it/wiki/service/task-scheduler)[When high CPU is normal: Guide](https://feex.it/wiki/software/system/when-high-cpu-is-normal)

## Sources and verification

Reviewed by Feex editorial. Last verified August 2026 Status: Feex Reviewed. [How we research](https://feex.it/wiki/research).

- [Microsoft Support: Compatibility Telemetry ](https://support.microsoft.com/windows/windows-diagnostic-data)· Diagnostic tasks
- [Microsoft Learn: Task Scheduler ](https://learn.microsoft.com/windows/win32/taskschd/task-scheduler-start-page)· Microsoft Compatibility Appraiser task
- [Foxhole process map ](https://foxhole.feex.it/)· First-party samples on Windows PCs. Not a lab benchmark.

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Quick facts

The short identity of this page. Specs, sources, and the full story stay in the article.

- **Type**: Windows Process

  **Publisher**: Microsoft Corporation

  **Executable**: CompatTelRunner.exe

  **Typical path**: C:\Windows\System32\CompatTelRunner.exe

  **Mapped by Feex**: Seen on Windows PCs in Foxhole

Feex Reviewed: Last verified August 2026

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Source: [Canonical Feex Wiki page](https://feex.it/wiki/process/compattelrunner.exe/)

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