If you are trying to run a Windows Service like the Diagnostic Policy Service and encounter an error instead that says, “Windows could not start the Diagnostic Policy Service”, worry not for this post will guide you on what you can do of the Diagnostic Policy Service is not running in your Windows 10 computer.
As you know, the Diagnostic Policy Service enables problem detection, troubleshooting, and resolution for Windows components on your Windows operating system. When you encounter this kind of problem, you will also see the “Access is denied” error message. This occurs when the “MpsSvc” process does not have the permissions needed for the Registry keys. This kind of problem happens when the TrustedInstaller account is missing the permissions for a Registry key and so to fix this issue, you need to take full control and ownership of the Registry keys.
You need to create a System Restore point first before you get started. This way, you can always undo the changes you’re about to make in case anything goes wrong. Once you’re done creating a System Restore point, refer to the following instructions to fix the “Windows could not start the Diagnostic Policy Service” error.
Step 1: Tap the Win + R key combination to open the Run utility.
Step 2: Type in “Regedit” in the field and tap Enter to open the Registry Editor.
Step 3: After opening the Registry Editor, navigate to this registry path:
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesDPSParameters
Step 4: After that, look for the “Parameters” registry key and select Permissions.
Step 5: Now select your account under Group or user names.
Step 6: Next, make sure that the “Full Control” and “Read” boxes are both checked, and then click on the Apply and OK buttons to save the changes.
Step 7: Afterwards, navigate to this registry key: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlWDIConfig
Step 8: From there, look for the Config key and right-click on it and select Permissions and then click on Add and type “NT Service/DPS in the box and click OK.
Step 9: Now select “DPS” and check the Full control box, click OK and exit the Registry Editor.
Step 10: Reboot your computer and check if the error is now fixed.