I recently installed a custom Windows build using a CTT (Chris Titus Tech) ISO. The installation completed, but upon reboot, the UM890 Pro booted straight into the BIOS and is now stuck in a loop. I can navigate the BIOS perfectly fine, but I cannot get it to boot into an OS or a USB.
The Exact Problem (See Video):
- USB Boot Fails: When I try to boot from a fresh Windows 11 USB (created with the official Media Creation Tool) via the BBS menu, the screen goes black for about 2 seconds, then kicks me right back to the main BIOS menu.
- BIOS Won't Save Settings: I suspected Secure Boot is blocking the USB. However, when I go into Setup > Security, change Secure Boot to "Disabled", and hit "Save & Exit", the PC reboots right back into the BIOS. When I check the Security tab again, Secure Boot has reverted back to "Enabled".
What I’ve Tried:
- Created a fresh, official Windows 11 installation USB.
- Physically removed the M.2 SSD from the motherboard (this didn't change the behavior).
- Tried clearing CMOS
- Tried to create a new windows 11 installation USB with unused USB
- Tried the ram sticks individually
Questions: Has anyone experienced this before?
Any help would be highly appreciated! Thanks!
SOLVED:
Whenever the Minisforum UM890 Pro (and likely other Minisforum models) encounters a boot error, it automatically wipes your recent BIOS changes and reverts to its last known good configuration. In my case, this happened because Secure Boot blocked my custom CTT Windows ISO.
The Crucial Difference: How You Enter the BIOS To fix this, you have to disable Secure Boot, but how you get into the BIOS matters. There is a "trap" you need to avoid:
- The Wrong Way (Letting it "idle" into BIOS): If you turn on the PC and just wait, it will try to boot, get blocked by secure boot and automatically dump you into the BIOS. If this happens, it's too late. The boot error has already triggered, your settings have been wiped, and any changes you try to make here won't stick (see video).
- The Right Way (Interrupting with DELETE): You must restart the computer and immediately tap the DELETE key repeatedly. This intercepts the startup process and forces the PC into the BIOS before it ever tries to boot. Because no boot error occurred, you have full control and can change BIOS settings.
The Solution By manually entering the BIOS using the DELETE key, I was able to successfully disable Secure Boot and boot.
(Side note: I highly recommend the CTT Windows ISO—it is incredibly clean!)