Restricting Waits in Vista
Because many device driver developers use Synchronous I/O Programming Techniques, Windows can slow down or "freeze up" while a device is taking time to respond. To reduce this problem, the I/O Manager in Vista will stop execution of programs that are "stuck" waiting for a device to respond after a few moments.
Note It is strongly recommended that Synchronous I/O Programming Techniques are avoided in your device driver. If Vista stops execution of your driver code because your driver is waiting for a device, your device may be left in an unknown state.