Windows boot manager on UEFI startup

Hi!

I have been using 4.1 for 2 weeks now. The BIOS boot settings was set to “Both, UEFI first”, and Qubes always started without any issues.

However after I finished the setup of a Win10 standalone HVM at restart the BIOS UEFI boot manager came up with two options; QubesOS and Windows Boot Manager. None of the options worked. Setting the BIOS settings to “Legacy only” solved the issue.

I am just curious if installing a windows HVM can somehow mess-up the boot settings. Or is it just a coincidence?

Just a quick update. It seemed that setting boot mode to “Legacy only” solved the problem. However in the last couple of days boot mode was set to “Both, UEFI first”. Other BIOS settings remained unchanged.

Do you have any idea what program changes the boot mode?