Use option "my devices is not detected"
Uninstall and reinstall WPRT.
Try LSRT.
Use different USB cables, USB ports other PC.
Keep trying.
Hard reset and try above suggestions again.
One of the above should work except if your USB port of your phone is damaged.
Unplug the phone from your PC and turn the phone off completely.
Launch WPRT and choose "My Phone was not detected" and then choose whether it's a Lumia or HTC.
Then when it is searching, connect the powered off phone to your PC
These are the steps I had to follow due to the phone turning off at the Gears screen after a few seconds. I just left it connected and after a minute or two WPRT had identified the phone