@RickardP, I had similar issues in the past - Windows can be a pain. I ended up doing a few things:
- Use a good USB cable
- Removed ALL the Core/Photon devices and drivers I had on my system. To do this, I used these command in a small batch file:
Once in Device Manager, you need to show hidden devices to reveal all the unconnected devices. Open the “Ports (COM & LPT)” item to see the COM ports assigned to Particle devices. You may also see other drivers setup by Zadig. I then uninstalled all the COM devices associated with Particle devices, including deleting their driver files (check box on the uninstall).
After clearing everything, I rebooted. Then connect you Photon, ideally to a USB2 port, put the Photon in Listening Mode and install the Particle Windows Serial driver for the Photon. Do this by manually selecting the driver (not auto detect). Then, put the Photon into DFU mode and install the Zadig driver for it. Repeat for each device you have.
If after all this Windows dosen’t properly find the Photon on USB then I have no more advice (install Win 10?!).