I'm trying to create a RAID 1 array on my XPS 8930.  I have two identical 2TB drives.  Both were RAID drives on another machine. I now want to set them both up as a RAID 1 array on the XPS 8930.  I selected Sata and RAID 1, then keep data on SATA disk 1, then confirm delete the data on the second disk.  Then IRST goes to work for a few seconds then an error pops up:

"An unknown error occurred while an operation was in progress.  The operation could not be completed."  I click ok and it says "The volume was ceated successfully" only it wasn't.  There is no array displayed in IRST.

The help option says reboot and try again... nothing else.  That didn't help.

Any suggestions?