>>TheFre+(OP)
Neither of my AM5 motherboards will allow QubesOS to install with Secure Boot on (and it's not going to be turned off) which really annoys me as I want to use it.
>>Dah00n+cs
The installer is likely not signed in a way Secure Boot trusts it. Verify the ISO yourself with the PGP key, disable Secure Boot, install it, re-enable Secure Boot.