The RTM and Service Pack 1 versions of the latest Windows client can fail to play nice with restarting multicore-processor computers, according to Microsoft. The Redmond giant indicated that both the 32-bit and 64-bit variants of Vista RTM and Vista SP1 could be impacted by the issue. However, it appears that the problem is more prevalent in scenarios in which the platform is used in tandem with virtualization solutions. Microsoft did not specify a CPU manufacturer, or a maker of virtualization software causing Vista to present end users with a stop message informing that the operating system is unable to access the boot device.

The software company described the problem as follows: "when you restart a multicore-processor computer that is running Windows Vista, you may receive the following Stop error message: "STOP 0x0000007B (parameter1, parameter2, parameter3, parameter4) INACCESSIBLE_BOOT_DEVICE." This problem is more likely to occur on a virtual machine."

Microsoft is offering end users a resolve for the stop errors returned by Vista, although the emphasis is placed exclusively on customers affected by this specific issue, who will have to contact the company directly. The hotfix delivered is not yet ready to be served to Vista's entire install base, and in this sense is an indication of the fact that the problem it is designed to fix, is not widespread enough to require an update. Traditionally the Redmond company includes all hotfixes for a specific Windows version into the next service pack which will be made available, but in this case there is a mention pointing to the possibility of an update.

"This issue occurs because of a race condition in which one thread reads some data that is being written by another thread. This race condition causes the PCI root node to be absent from the device tree. Therefore, the system generates a Stop error because the storage device that the system relies on is missing," Microsoft explained.