Windows 10: Can't install up Windows on USB flash drive during setup

I have Windows 1803 and it keeps urging me to upgrade. I installed the windows upgrade assistant. It downloads 1903, but then tells me it can't be installed on a USB flash drive.
Thing is, I don't have a USB flash drive on the system. I have a SSD, but Windows can be installed on a SSD, can't it?

And, just recently, when I update the system and it restarts, it comes up with some error message about not being able to boot on an Flash drive. I turn the machine off and back on, and it boots up just fine.

Any idea what is going on?

:)

 

"You can't install Windows on a USB flash drive using Setup."

Thank you; it worked for me. (Although your suggestion should say from 1 to 0).

 

Installing windows off of a USB stick

Step By Step from vista:
From admin cmd prompt

1. diskpart
1a. list disk
2. select disk 1 (replace 1 with your usb drive)
3. clean
4. create partition primary
5. select partition 1 (replace 1 with your usb drive)
6. active
7. format fs=fat32
8. assign
9. exit

Copy Windows Vista's DVD ROM content to the Flash Drive

xcopy d:\*.* /s/e/f e:\ (d being your vista cd and e being your usb stick)

And that's it, boot off your usb disk

 

"You can't install Windows on a USB flash drive using Setup."

I finally ended up upgrading from W10 IP Build 14936 to 14951 thanks to the proposed registry editing.

Please, be careful....

There's another post on Microsoft boards that suggests to mark the OS partition as "active" if it's not.

I did it and I had to fix then the OS using an W10 install media (Startup Repair).

So this registry fix do the trick perfectly with no other interventions.