I really need help upgrading my phone to Windows 10 or revert to Windows 8.1. I am in the insider program and started downloading the Windows 10 OS and it suddenly started restarting constantly. I have tried to hard/ factory reset my phone and tried using the Windows Phone Recovery Tool, but my phone will not stay on long enough to connect to my pc/ hard reset. If anyone has any suggestions or solutions for my problem I would HIGHLY appreciate it . BTW I have a Nokia Lumia 635 which I upgraded from 8.1 to 10.