12-30-2016 02:01 PM
Has anybody else experienced this? I would STRONGLY recommend that you DO NOT upgrade to 1.43 as it will break keep you from being able to boot up consistently. It does not matter if you have a current install or try to reinstall, Windows will not boot up most of the time.
I found https://support.lenovo.com/us/en/solutions/SF16-T0079 and it does not state T420, probably because it is no longer under warranty, but this issue was definitely introduced with 1.43 and Lenovo released this buggy BIOS code to many models not listed.
Below is part of the release notes.
CHANGES IN THIS RELEASE
- Security fix addresses LEN-8324 System Management Mode (SMM) BIOS Vulnerability.
If the UEFI BIOS has been updated to version 1.43 or higher, it is no longer
able to roll back to the version before 1.43 for security improvement.
[New functions or enhancements]
- Fixed an issue where the brightness control might not work on Windows XP.
Lenovo, please update this BIOS for ALL AFFECTED MODELS ASAP so that those of us who have made the mistake of upgrading to it can continue to use our computers!
01-05-2017 07:49 AM
Lenovo, any update on this issue? I still have multiple T420s's that no longer function due to this bug in your BIOS update. Please respond as I cannot apply your workaround as I cannot get Windows to boot up. I'm sure others will be in the same boat if they attempt to install Windows.