Minimal BASH-like line editing is supported...OS cannot boot

I installed only OpenSUSE Leap 42.3 on my PC. I didn’t do anything special yesterday, but this morning, the system cannot boot.

The screen show the following content:

**Minimal BASH-like line editing is supported. For the first word, TAB lists possible command completions. Anywhere else TAB lists possible device or file completions.

**What is the problem, how to solve it? Many thanks.

I don’t really know for sure.

What you describe sounds like the grub2 prompt. But it could be a dracut prompt. I can’t be sure.

Are you getting any kind of boot menu at all? If not, then something went wrong with the grub2 install.

Did this ever boot properly?
Are you using UEFI booting or Legacy booting?
Did you use UEFI booting or Legacy booting when installing openSUSE?

I’m sorry for replying so lately.

The system worked very well, it broke very suddenly, I didn’t do something that seems to hurt it.

I installed openSUSE using Legacy booting, but I’m not 100% sure.

Not a problem.

Did you fix your system in the meantime? Or are you still unable to boot?

I installed openSUSE using Legacy booting, but I’m not 100% sure.

Okay, that seems likely. This problem is less likely to happen with UEFI booting, though you can have different problems.

Here’s a wild guess. Sometimes openSUSE install booting from the extended partition. That works well, but it is not a place from which booting is fully supported. So some other software (could be Windows software) might have removed that boot code from the extended partition.

If you still have that problem, try google for “Super Grub Disk” (or, I think you need “Super Grub2 Disk”). That can probably boot you into your system. And then you can use Yast bootloader to reinstall booting.

Check that the boot flag is set to your root partition.