Today, our help desk received a frantic call from a user stating she rebooted her Lenovo Thinkpad SL500 laptop and was booted into the BSOD and that Windows XP would no longer boot. The message would briefly display on the screen before rebooting. I had our Help Desk Analyst choose the option to disable automatic reboots and we could finally see the error the BSOD was reporting.
Stop 0x000007B INACCESSIBLE_BOOT_DEVICE
We have encryption software installed on the laptop and my first though was something had happened to that. We went through the recovery steps to decrypt the drive, but the BSOD still would occur. I then thought the Master Boot Record was corrupt, so using a partition tool I viewed the configuration. I found a new partition had been created on the drive, but any attempts to return to the original settings did nothing.
As a last resort, I suggested the Help Desk Analyst look at the BIOS to determine the AHCI setting on the SCSI Hard Drive. Low and behold, it had switch from Compatibility mode back to AHCI. My only guess was that whatever created this new partition, also reconfigured the BIOS. Luckily this did the trick and the user’s files were safe.
My Windows System Administrator 
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