I encountered the prohibitory sign on startup. I tried all of the possible fixes, none worked, so I was left with erasing the hard drive and reinstalling because the iMac wasn't seeing the built in drive. So I did.
I tried to migrate from my time machine drive and it kept telling me there wasn't enough room to migrate just about anything. I looked at info via disk utility and it appears I have about 4 to 6 gb of space on a computer which had 3tb before all this started.
I'm running Mojave. on a late 2015 27" iMac
PLEASE HELP ME. MY WORK RELIES ON THIS MACHINE AND I CANNOT AFFORD A NEW IMAC RIGHT NOW.
I AM BEGGING