Question System Crash now Legacy Mode boot only

Jul 21, 2019
3
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I had a system crash. The windows stop code was 0xc000021a. When the blue stop code screen would appear it would say it needs to reset then the computer would just shut down. This all happened when I was trying to recover to a prior system date and then the computer encountered an error during this process and shutdown. I could not start in safe mode to troubleshoot. My system is an Aurora R7. I had a windows boot disc but had not backed up anything so I had to do a fresh install. The problem is unless I disabled safe boot mode and enabled legacy boot the bios would not recognize the cd drive and I would not be able to boot from it. I also tried the windows media creation tool but even in Legacy mode my CPU would not recognize the USB drive even in legacy mode. I was able to reinstall windows 10 on my SSD from the CD but now I cannot boot if in safe boot mode and it will only boot in legacy mode because this is the only way I could get my computer to use the boot disc. Basically id like to have secure boot enabled tp prevent boot time viruses but I fear I cannot boot UEFI because I had to do the install in legacy mode. Can anyone help me sort this out?
 

Lutfij

Titan
Moderator
Are you on the latest BIOS update for your Dell/Alienware? You should be able to switch from Legacy mode to CSM mode in BIOS. You could also try and remove the CMOS battery from the board(after the system is powered down) and see if replacing it after 30 mins gets you back to default settings...?
 
Jul 21, 2019
3
0
10
Can you boot from legacy mode to check if the boot drive volume is MBR? (Master boot record).

I can boot into windows from legacy mode. I cant find any information about boot drive volume.
Can you boot from legacy mode to check if the boot drive volume is MBR? (Master boot record).

Yes the boot drive volume is MBR. I was able to check. If I try to boot up in safe mode through the msconfig property changes windows just boots into safe mode
 
Jul 21, 2019
3
0
10
Are you on the latest BIOS update for your Dell/Alienware? You should be able to switch from Legacy mode to CSM mode in BIOS. You could also try and remove the CMOS battery from the board(after the system is powered down) and see if replacing it after 30 mins gets you back to default settings...?

What is CSM mode? The only other option is UEFI
 

Feren142

Reputable
Jul 14, 2019
99
14
4,565
What is CSM mode? The only other option is UEFI
CSM stands for compatibility support module. It lets you run, recognize and boot legacy stuff which is why I asked you if your drive volume was MBR, which is old.

There is a Console command added to windows 10 which allows you to convert a MBR drive/volume to GPT, which is the modern volume.

Edit:
You cannot boot a MBR volume if you’re using UEFI. I’m wondering if maybe when you reinstalled windows you accidentally used MBR which would cause it to not show up in UEFI boot menu.
 
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