Chosen Solution
iMac won’t start up and it shows the “Prohibition Sign” on start up. I went into recovery mode and to disk utility and it doesn’t show my fusion drive and it shows no information what so ever. Can anyone help me?
You won’t see the Fusion Drive under Disk First Aid, You’ll see the discreet drives (HDD & SSD) that combined make up the Fusion Drive set. If you can’t mount the drives then you have a deeper problem! At this point you’ll need to use the command line interface of Core Storage following this guide: Fixing a Mac Fusion Drive that Disk Utility can’t erase
Sounds like your fusion drive has failed. Try to get ahold of another mac and make a bootable thumb drive for any OS X installer. See if your iMac will boot from this thumb drive. This would verify if your disk has failed or not.
