I've got the same problem as in this thread but the fix instructions don't work for me. http://en.community.dell.com/support-forums/laptop/f/3518/p/19477302/20234628.aspx
In short, no matter what I try, I just get "An unknown error occurred while an operation was in progress. The operation could not be completed" when I select Accelerate Disk or Volume and click OK. Like the original poster, I've tried different SSD sizes, all to no avail.
I've followed the instructions as closely as I can, so I am able to clean the SSD, enable iRST and restart. I don't get the CTRL-I prompt so I'm guessing that's peculiar to the poster's XPS 14 (L421X).
Can someone from Dell give me similar instructions for the Ultrabook 14z running Windows 8, please?
Solved! Go to Solution.