When attempting a unified bare metal recovery (UBMR) you are presented with the error BIOS Mismatch
Typically this is: The Selected Client is Legacy and the local BIOS is UEFI, The Selected Client is UEFI and the local BIOS is Legacy
BIOS mismatch error (NOT UEFI)
The original backup must match the BIOS type which is being restored.
For example, on new system using UEFI, the bios must be configured for UEFI only, not Legacy. However, if this is set for MBR you would want to ensure UEFI is disabled.
This will also be important for the ISO media. When you create the USB media be sure you are using a utility which allows you to configure the boot mode. Such as the utility called Rufus. On UEFI systems you will want to be sure GPT is selected, or for the legacy system be sure to use MBR using the FAT32 Filesystem.
This is usually because the BIOS is configured for UEFI boot or a RAID card is making us detect the system as UEFI.
You can override this check by adding BiosType=1 under the [BProfessional] heading of the master.ini file of the BMR disk for Legacy restores.