Windows 10 Black Screen with cursor

I have a working installation of Windows 10 on my internal SSD (MacBookPro13,2) but i wanted to transfer it to my external SSD (thunderbolt). After cloning it i can boot from the external SSD but after the windows logo the screen stays black and i can only see a cursor and a circle. Switching to EFI mode works but after that it doesnt change anything. Legacy mode doesnt work as it says the drive is not mountable… any suggestions?

If you hold the option key down when starting, does it show the drive? Does it show up in Startup Disk? Did you try in a different thunderbolt port?


Hi Tim,
Thanks for the reply.
I could see and Start with the option key while startup. However I can’t see it in Start Up disk.
Tried different Thunderbolt ports as well.

I suspect that Windows is booting up but when it moves from the EFI boot to booting windows and Windows tries to load the driver for the drive, it fails. Legacy would not work, since external booting only works reliably with EFI booting. it is possible that your model of Mac doesn’t support external booting. If you would like a refund, please submit a request here: