after many days fixed my Network Troubleshooter on 8.1
the Diagnostic Policy Service was starting then stopping

The Diagnostic Policy Service service on local computer started and then stopped. Some services stop automatically if they are not in use by services or programs.
seen so many sites with ideas that just didn't work i headed over to sevenforums and found my answer there.

I didn't have any restore points go back on
I used tweaking.coms windows repair to restore registry, file permissions and reset winsock and dns but nothing helped my problem.
seen so many posts on the web from System file Scanning, uninstalling network adapters, set DPS Registry Permissions and using cmd prompt to assign networkservice and localservice with administrators.

in my case it was something to do with Performance monitor --> DiagLog was disabled
so renabled and restarted machine DPS was working again.

my question is why is it so hard to diagnose the trouble shooter itself?