Last weekend my iMac started to act in a very strange way. While I was working, my Mac was very slow and the mouse and keyboard didn't respond very well.
So I decided to reboot because having two users and switching from time to time, the memory could be the problem. But when I rebooted the other user was gone, and the Mac still was very slow. I rebooted several times and nothing changed, so I decided to try to reinstall El Capitan which was the latest version that I have – originally the Mac came with Maverick.
Then everything went wrong, the system couldn't complete the installation, I tried to erase the disk, I tried to repair the disk and several errors occurred,
To make this story short, I finally succeeded installing Maverick, but then I realized that it was installed in the 122.33 GB Apple SSD because the 3TB Fusion drive couldn't be formatted. Trying several time, the disk was finally erased and I ran several verification and repair passes and everything looks OK according to Disk Utilities.
But Mavericks is still installed in the 122.33 GB Apple SSD and it looks like the 3TB Fusion drive can't be recognized, partitioned or deleted, so I am very desperate.
Here are the screenshots:
I already followed this instructions here, but they didn't work. I don't recall the message but it didn't work
I hope somebody can help me, I am not under warranty and I have two Times Capsules back ups, so I don't care about the information.
Best Answer
I would suggest following the steps in the answer posted here
Most importantly:
diskutil cs create "Macintosh HD" disk0s2 disk1s2
Your diskutil output should look more like this with the "logical volume"
And Core Storage list like this: