Installing Proxmox on my HP EliteDesk 800 G2 from USB fails with a “Selected boot image did not authenticate” error because of Secure Boot. Disabling Secure Boot in the BIOS isn’t enough — the setting reverts unless I also type in the confirmation number HP prompts for after I save and exit, which is easy to miss. I include a short bonus section on enabling Virtualization Technology (VTx) when Proxmox reports no KVM support...
