Cannot boot to an external drive containing an image file

@Jim_Hill  One additional note. If your previous setup involved disabling Secure Boot, it probably also enabled Legacy BIOS mode, and you were probably booting in that mode, as opposed to UEFI without Secure Boot. That’s not a great idea with Reflect Rescue Media. You should always boot the Rescue Media in the same way as you boot the regular OS. Not only is that more convenient, but Reflect’s “Fix Boot Problems” wizard attempts certain fixes based on how the Rescue Media itself was booted. So if you boot it in Legacy BIOS mode and have it try to fix an OS that’s set up for UEFI booting, it will attempt the wrong fixes.

I suspect your issue here is that you don’t have a FAT32 partition, which would prevent UEFI booting on most systems. There’s a difference between simply disabling Secure Boot while still booting in UEFI mode and disabling Secure Boot in order to boot in Legacy BIOS mode.

I guess I'm not actually returning to the legacy mode, but I still need to disable secure boot mode, so I can boot from an external device..

Jim

@Jim_Hill  No you don’t need to disable Secure Boot as long as your bootable environment supports Secure Boot. Windows 8 and above (and therefore WinPE 4.0 and above) support Secure Boot, so if you build your Rescue Media using a WinPE/RE kernel of that release or newer, you can boot Rescue Media with Secure Boot enabled. I do this on a regular basis. Use the F12 one-time boot menu to select your boot device.

But as mentioned above, you should really be using a flash drive for Rescue Media, not booting from the hard drive that contains the backup. Some systems don’t support booting from USB fixed disk class devices (SSDs and HDDs) and instead only supports USB removable storage class devices (most flash drives), so that could be a problem all on its own. But more importantly, in order to boot in UEFI mode, your bootable environment will need to reside on a FAT32 partition. That’s a terrible file system to use for an entire hard drive these days, so if you really want this and your system even supports it, you’d have to create a small FAT32 partition specifically to store your Rescue Media files, while keeping everything else on an NTFS/exFAT partition that occupies the rest of the disk.

But again, you should really consider having Rescue Media on a dedicated device that you only connect when you need to use or update it. Yes it’s less convenient, but suppose you got hit with malware or ransomware, exactly the sort of incident you might want to use your Rescue Media to recover from. If the malware/ransomware wiped your external hard drive because it was online since you always have it connected, now your Rescue Media is gone, so you have more of a hassle to deal with before you can restore a backup (assuming any backups were still available, which paid versions of Reflect attempt to help ensure through the Image Guardian feature.) But if your Rescue Media was instead on a device that wasn’t even connected at the time, it will still be intact.

Create a Reflect UEFI-compliant rescue flash drive:

https://knowledgebase.macrium.com/display/KNOW7/Creating+rescue+media

With that connected, press F12 at powerup to boot from it.  You will also need to have the drive containing the image you want to restore connected to the system (unless the image is also on the flash drive).

Sorry, but I have some non-computer issues that I must take care of immediately.

I appreciate the answers, but will need to respond tomorrow.

Jim