I'm kind of a novice here, and I think I got in over my head. I was trying to do a clean install of El Capitan on my 5K iMac. It has a 1TB Fusion drive.
I booted from a USB drive, entered Disk Utility, clicked the single partition I saw under the Fusion Drive, then erased it (pretty standard.. done this before). I was given some kind of error, then the partition disappeared.
Now, whenever I boot my computer and open Disk Utility, it looks like this:
No partitions under Fusion Drive. Clicking the Partition option doesn't give me any options (everything is greyed out and non-clickable). Clicking the First Aid option doesn't work either. It pops up a window asking if I want to Run or Cancel. Clicking on either does nothing. The window just sits there.
Like I said, I'm kind of a novice, so I don't know what to do from here. Any help, please!?