Stop 7B Error (Inaccessible_Boot_Device)

Motherboard upgrades on a machine running Windows 2000 Professional/Server can cause a BSOD (Blue Screen Of Death) failure at boot up, with the message :-

STOP 7B INACCESSIBLE_BOOT_DEVICE

There can be a number of reasons for this error, including IRQ conflicts between devices on the new motherboard. However, a likely cause in the case of a motherboard upgrade is the fact that the Operating System does not have the correct drivers to access the boot disc (the main hard disc). This can be because the drivers installed by Windows 2000 when it was loaded with the old motherboard can only handle IDE hard disc communication at ATA33/66, and the new motherboard supports ATA66/100.

Some information on the solution to the problem can be found at http://support.microsoft.com/default.aspx?scid=kb;en-us;Q271965, which shows how to import all the IDE drivers into the registry prior to moving the hard disc to the new motherboard.

The basic procedure is as follows :-

• Replace the old motherboard and boot up the machine to Windows 2000.
• Extract the driver files Atapi.sys, Intelide.sys, Pciide.sys, and Pciidex.sys from %SystemRoot%\Driver Cache\i386\Driver.cab on a machine running Service Pack 1, or from the Service Pack 1 installation disc, and copy them to '%systemroot%\system32\drivers' on the problem machine. You can download these drivers, and the REG file required in the next step, from here.
• Apply the registry file IDEdrivers.reg (downloadable from here).
• Close down the machine.
• Replace the new motherboard.
• The machine should now boot past the Stop 7B error previously experienced.