Lenovo T495 R12HT51W BIOS update may cause Windows 10 to not load during system start-up. It may not be related to Windows updates KB4552931 and KB45565799 because I have those updates in my system before upgrading to that version of UEFI BIOS and ECP (Embedded Controller Program).
R12HT51W BIOS Update
I have this habit of keeping my system up-to-date. That is part of getting value for my money. But after the troubles I got as a result of upgrading my BIOS to R12HT51W, I am breaking the habit. Don’t update BIOS unless it is vital.
My Lenovo T495 Prior R12HT51W
My Lenovo T495 is an AMD-variant that runs Microsoft Windows 10 Pro Version 10.0.18363 Build 18363. Meanwhile, the BIOS version and date are R12ET50W(1.20 ) and 2/19/2020.
How The Issue was Isolated
At first, I was not sure the problem is caused by R12HT51W because the recent Microsoft Windows 10 updates also caused problems on other people’s systems.
With no luck of getting Windows 10 load successfully by tweaking BIOS configuration, I decided to reset my PC but keep my files. The option reinstalls Windows 10 without deleting your data. However, it also uninstalls your applications. Once your system is back, you may encounter some permission issues with your existing folders and files.
The reset is done via the Troubleshoot tool for Windows, which is accessible via the F11 option on the BIOS screen on system start-up.
Then, choose “Troubleshoot.”
Then, choose “Reset this PC.”
Finally, select “Keep my files.”
The reset takes around 45 minutes, depending on your machine’s specifications. Once within Windows 10, I disabled Windows updates. I also uninstalled KB4552931 and KB4556799.
I was able to restart Windows 10; then, I installed Docker for Windows, which requires a system restart. Windows 10 failed to start up this time.
How to Fix The Problem
The problem caused by the Lenovo T495 R12HT51W BIOS update can be fixed by installing the previous version (R12ET50W) of the UEFI BIOS and ECP.
Download R12ET50W from this Lenovo Support website.
Run the executable file.
You may get this error during the setup.
You need to disable the Secure Rollback Prevention first in the BIOS configuration to install an older version of UEFI BIOS and ECP.
Lesson Learned
Never update BIOS firmware unless you really need to!