You have a Hyper-V guest operating system that is running Windows Server 2008 R2 or Windows 7.
The guest operating system has a disk that is connected to a SCSI controller.
In this scenario, the following event is logged in the System log:
Log Name: System Source: VDS Basic Provider Date: date time Event ID: 1 Task Category: None Level: Error Keywords: Classic User: N/A Computer: computer name Description:Unexpected failure. Error code: 490@01010004
The Virtual Disk Service (VDS) looks for the Location paths property of the controller. The value of this property is the path location of the disk. However, a virtual controller does not have this property.