We began using the Sophos Advanced Endpoint / Intercept X / Sophos Drive Encryption package for ourselves and one of our customers as a trial for the past few months.
Over the last 3 business days, I've had 3 separate Windows 10 Lenovo laptops of my customer enter a "boot loop" where:
Lenovo hardware diagnostics of the hard drive come up clean, but we're unable to boot to that local install of Windows in any way, even through various safe modes and recovery modes. The operating system just seems too damaged to boot. We were able to browse the files eventually by using the method in this article here for hooking up the hard drive as a secondary drive elsewhere and unlocking it with the recovery key: http://woshub.com/data-recovery-on-a-damaged-hard-disk-encrypted-with-bitlocker/
We also know that in at least 1 of these cases, the machine went through a "hard shutdown" (the user's OS crashed and they had to hold the power button down until the machine powered off) immediately before this issue. It's possible that the issue that caused the hard shutdown was also the cause of this boot loop issue, or it's possible the hard shutdown itself was what damaged the critical bitlocker section of the drive, or maybe it's something else entirely.
Has anyone else experienced this issue and have any suggestions for getting to the root cause? Out of ~50 machines for this customer, having 3 of them fail in this exact same way in 3 business days is alarming. Because the last things the users see before the boot loop occur is the Bitlocker screen, they immediately assume BitLocker / Sophos Encryption is to blame, and may as a knee-jerk reaction have us remove it entirely from their network. I'd like to not have that happen, as this would slow down or halt the rollout of Sophos Endpoint across our customer base.
Some other notes:
Is this a Windows Defender Secure Boot issue maybe - support.microsoft.com/.../update-for-windows-defender-antimalware-platform
Thanks Andy, but it wasn't this issue. Even when we disabled secure boot in the BIOS as part of our troubleshooting, we still couldn't boot into any form of Windows (even safe mode, etc.)
Is it possible the 3 culprits are missing some firmware update that the others have?
Compare the bios of a functional computer to one of the down ones?
Respectfully,
Badrobot