Extreme 4 - Turned of Boot Mgr

Two ways to clear the CMOS/BIOS: One is by using a jumper on the board.

The simpler method is using the CLR CMOS button on the board's IO panel. That button is just under the PS2 inputs at the very top of the IO panel.

First, you must shutdown the PC, shutoff the PSU and unplug the AC power cable from the PSU.

Wait about 30 seconds for residual power in the PSU to dissipate. Then use a small screwdriver, Q-tip, or the plastic tube from the canned compressed air used to clean PCs, to push that button in and hold it down for several seconds.

When you are done connect AC power to the PSU, turn it on and start the PC. Clearing the CMOS/BIOS causes all the options in the UEFI/BIOS to be reset to their default values. When the PC boots after a CMOS/BIOS clear, you will be prompted to enter the UEFI/BIOS to reset any options you use, or to just accept all the default values.

If you use many non-default settings in the UEFI, save them in a profile before clearing the CMOS/BIOS. You may then restore them by loading the profile with two mouse clicks, rather than all the work of setting them manually.

When I asked about installing Windows 10, I know you have only one drive (SSD) where you installed Windows.

What I mean is did you have any other disk drives connected to the board and powered up when you installed Win 10 on the SSD? My guess is that you had at least one other drive running when you installed Win 10.

If you have more than just the OS drive running when you install Windows, the Windows installer program will put the MBR or GPT (boot) partition on a drive other than the target OS drive. Why the Windows installer does that is not clear, but I can assure you it does.

When you disabled the Boot Manager in the UEFI/BIOS, it seems to have excluded the other drive with the boot partition from being included in the boot process. I can understand why that was done in general by the Boot Manager, but that will cause the issue that you now have.

Clearing the CMOS/BIOS should restore things to normal. Just don't touch the Boot Manager option, and in the future always install Windows with only the OS drive powered on in the PC.

If you still have a booting issue after clearing the CMOS/BIOS, let us know.

Did you try clearing the CMOS/BIOS on your board to fix your problem?

I'm not sure what you mean by "... turned off the boot manager...", and back on again. Did you do that in the UEFI/BIOS? Please describe that in more detail for me.

Are you saying the PC won't boot now because "boot manager" is missing?

Did you install Win 10 with more drives than just the SSD OS drive in the PC?

ASRock has many different boards that are "Extreme4" models, please provide the full model name for us.