Question Unable to boot to Windows 10 -- "The system has POSTed in safe mode..."

[kpaik1]

I have an Asus Z 390-E Gaming motherboard. Ever since I updated my BIOS version from 0506 to 2004 using EZ Flash 3, I’ve been receiving a notification during the boot process saying, “The system has POSTed in safe mode. This may be due to the previous POST attempt failing because of system instability, or if the power button was held in to force the system off.” Why did I update my BIOS? I was troubleshooting an earlier GPU/game-crashing issue, and an NVIDIA tech support rep recommended I do so because it “might help with general system stability”. I was skeptical, but also keen to solve my issue then.

Anyway, now as a result, I’m not able to boot into Windows 10. Prior to updating my BIOS, my PC had no booting problems. Has anyone run into this issue before, and if so how did you resolve it?

Things I’ve tried so far with no success: changing GPUs, restoring BIOS defaults, and clearing my CMOS. Asus technical support was suggesting I send my mobo in for investigation/repair, but I’m not jazzed about dismantling my PC and watercooling loop unless I know it will help.

 

[CountMike]

I have an Asus Z 390-E Gaming motherboard. Ever since I updated my BIOS version from 0506 to 2004 using EZ Flash 3, I’ve been receiving a notification during the boot process saying, “The system has POSTed in safe mode. This may be due to the previous POST attempt failing because of system instability, or if the power button was held in to force the system off.” Why did I update my BIOS? I was troubleshooting an earlier GPU/game-crashing issue, and an NVIDIA tech support rep recommended I do so because it “might help with general system stability”. I was skeptical, but also keen to solve my issue then.

Anyway, now as a result, I’m not able to boot into Windows 10. Prior to updating my BIOS, my PC had no booting problems. Has anyone run into this issue before, and if so how did you resolve it?

Things I’ve tried so far with no success: changing GPUs, restoring BIOS defaults, and clearing my CMOS. Asus technical support was suggesting I send my mobo in for investigation/repair, but I’m not jazzed about dismantling my PC and watercooling loop unless I know it will help.

Ty switching between CSM/Legacy and UEFI modes.

 

[kpaik1]

Ty switching between CSM/Legacy and UEFI modes.

Thank you for the reply! I tried booting with:

1. Launch CSM (Enabled) > Boot from Storage Devices (Legacy only)
2. Launch CSM (Enabled) > Boot from Storage Devices (UEFI only)

Unfortunately, I'm still getting the “The system has POSTed in safe mode" notification in both cases.

One interesting observation from recent troubleshooting however:

1. When I have my RTX 3090 installed and select Boot Override > Windows Boot Manager (Samsung SSD), the computer tries to reboot then gives me a blue screen error before restarting itself. (this sends me back to “The system has POSTed in safe mode" notification.)
2. When I have my old GTX 970 graphics card installed and select Boot Override > Windows Boot Manager (Samsung SSD), I'm actually able to get into Windows 10! (however if I restart the computer I end up back in the “The system has POSTed in safe mode" notification.)

Any insight into why this might be?

 

[CountMike]

Thank you for the reply! I tried booting with:

1. Launch CSM (Enabled) > Boot from Storage Devices (Legacy only)
2. Launch CSM (Enabled) > Boot from Storage Devices (UEFI only)

Unfortunately, I'm still getting the “The system has POSTed in safe mode" notification in both cases.

One interesting observation from recent troubleshooting however:

1. When I have my RTX 3090 installed and select Boot Override > Windows Boot Manager (Samsung SSD), the computer tries to reboot then gives me a blue screen error before restarting itself. (this sends me back to “The system has POSTed in safe mode" notification.)
2. When I have my old GTX 970 graphics card installed and select Boot Override > Windows Boot Manager (Samsung SSD), I'm actually able to get into Windows 10! (however if I restart the computer I end up back in the “The system has POSTed in safe mode" notification.)

Any insight into why this might be?

You should be able to do this in safe mode
https://www.tenforums.com/tutorials/16397-repair-install-windows-10-place-upgrade.html
Choose to keep personal files.

 

[kpaik1]

You should be able to do this in safe mode
https://www.tenforums.com/tutorials/16397-repair-install-windows-10-place-upgrade.html
Choose to keep personal files.

Thanks for the suggestion! Based on what I've read around similar issues, I was optimistic that a reinstall of windows would help.

I tried it today and unfortunately: no changes in what I'm observing compared to Aug 3/I'm still experiencing my original issue.