Detects Error EventID 9 in the System Log. This error indicates that I/O time-out has occurred within the storage system, ...

                        Detects Error EventID –9 in the System Log. This error indicates that I/O time-out has occurred within the storage system, as detected from the driver for the controller. 
                        http://support.microsoft.com/kb/259237  
                        http://support.microsoft.com/kb/154690