I am still unable to backup using WHS but now I get this massgae:
"The computer failed to take a snapshot of the volume for backup. System.IO.FileNotFoundException: The system cannot find the file specified (Exception from HRESULT: 0x80070002) at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRIn"
I also looked at the computer event log and found some error masages:
The driver detected a controller error on \Device\Harddisk2\DR2
The shadow copies of volume C: were aborted because of an IO failure on volume C:.
simply by using check disk, you've pretty much isolated it as a hardware problem. although if you have the data backed up, you could attempt to write 0s to the drive. by writing to every block, that allows you to test every block of the drive. but no guarentees. and you'd lose everything on the drive. as for obtaining an RMA and/or contacting intel about this, the page you likely would need is the link below.
hope this is of help. and my best to a quick solution