I installed software for a Canon Sureshot S230. After that, I get a blue screen with the IRQL_NOT_EQUAL_OR_LESS only when I shut windows down. I unistalled the drivers and software as it was the only new thing I installed in about 2 months. I still get the error. I know it is related to a device driver, but how can I tell which one is causing this. I never had this problem until I installed the new software. Canon is no help since the responded with a generic response. Its no big deal in a way, since it is only when I restart or try to turn off the PC, but it is just annoayhing.