T480: Win10 external USB-SSD no longer boots after update from 1909 to 20H2 but on other hardware its working

[mortimar]

Hello all,

I am using an external USB-SSD with WIN10 Pro and used to boot from it no matter if connected to USB-C or USB-A ports.
After the update from 1909 to 20H2 it no longer boots normally.
It gets to the little circle and rotates that for some time until the dots of the circle freeze.
It still boots in safe-mode.
But 'Win10 clean boot' does not work.

Strangely on another hardware and with VirtualBox I get it to boot normally.
More strangely it does boot normally when I run it as an internal drive but that is not really an option.
Also tried another enclosure with same result.

Has anyone an idea what I could do to get it back to normal boot?
Is there maybe a 'Microsoft service' I should remove in addition to the non Microsoft services for a clean boot?

It's a GPT formatted SSD. Secure Boot is on. There is another SSD (NVMe) build-in encrypted with bitlocker.

Thank you very much for reading and any suggestions.

bye morT

[davidgurvich]

You could try macrium reflect rescue and select the fix boot problem option. Could also be a problem if you cloned a drive.