Disabling Windows Compatability Telemetry

Did not fix it for me either.  It seems to get triggered by running games on my computer.  Perhaps using certain API's triggers it?

(1) It was installed without authorization, and I think reinstalled after I managed to remove it.

(2) It had no legitimate business on my computer.

(3) It caused serious performance issues until I figured out how to destroy it.

These are all characteristics of malware, although the fact that its creator did not actually intend it to cause damage must be kept in mind.

rofl

seriously

just because software behaves erratically and in an unwanted manner does not make it malware

the compatibility telemetry runs fine on my machine, but on my son's machine gets 100% disk usage for apparently no reason

not everyone has the same issues with it and labeling is malware just shows your ignorance

Have you tried disabling the trigger in the task scheduler?

Didn't fix the problem.  I've got the Connected User Experiences and Telemetry service disabled and I still see CompatTelRunner.exe taking up to 100% of my disk usage for many minutes after startup.  Incidentally, another way to disable the service is to open a Command Prompt (Admin) and enter the following command:

  sc config diagtrack start=disabled

Don't forget to stop the service if it's running:

  sc stop diagtrack

      OR

  net stop diagtrack

You can always verify that it's disabled by hitting Win + R and typing services.msc to open the services dialog and scroll down to Connected User Experience and Telemetry.

But, alas, disabling this service, no longer resolves the problem.  We need to discover what else starts the CompatTelRunner.exe program.