Windows 7 Blue Screen Of Death with error 0x7B

If you ever had to change the motherboard of your computer and wanted to keep the Windows installation on it, you might have encountered the dreaded Blue Screen of Death with an unhelpful error code.

In my case, this was a Windows 7 installation where the on board SATA controller started to misbehave. These problems didn’t show up in Windows but only when I did my weekly backup using CloneZilla. I wonder what would have happened if I had happily continued to use this computer because Windows didn’t warn me?

First I put the hard disk into a different computer, started CloneZilla and made a backup. No errors showed up, so it wasn’t the hard disk but the controller.

Then I threw out the old motherboard and took a new (cheap) one that still supported my old Dual Core processor and RAM. Connected everything and booted the box. I was expecting for it just to work. This is Windows 7, one of the most modern operating systems available, so driver issues should be a thing of the past, right?

Well, not so. Windows 7 crashed and rebooted, crashed and rebooted, crashed and rebooted. After a while I got tired of this 😉 , pressed F8 for the boot menu and disabled automatic reboot on errors. Then I got the BSOD in all it’s glory: Error code 0x7B, meaning “INACCESSIBLE_BOOT_DEVICE”.

In the olden (Windows XP) days this was a symptom of the SATA controller running in AHCI mode and Windows expecting IDE mode or vice versa. Apparently this is still the same with Windows 7 (When will you ever learn, Microsoft?).

Unfortunately the new board’s BIOS did not really allow me to switch the SATA mode (it seemed to allow me, but it didn’t make any difference). So after swearing a lot I turned to Google and found … a lot, most of it not really helpful. Hours (literally!) later, the solution turned out to be the following:

To allow Windows 7 to boot in IDE as well as AHCI mode, I had to enable the following drivers (by setting “Start” to “0” in the registry, there might be other options to do this):

HKLM\System\CurrentControlSet\services\intelide
HKLM\System\CurrentControlSet\services\pciide
HKLM\System\CurrentControlSet\services\msahci
HKLM\System\CurrentControlSet\services\iastorV

The first two allow Windows 7 to boot from SATA in IDE mode. The second two allow Windows 7 to boot from SATA in AHCI mode.

So, why isn’t that the default? I have no idea.
(Do I have to point out that Linux booted on the updated box without any problems? Which one is the more user friendly system?)