iMac shut down unexpectedly, won’t restart
I have an iMac 24 running Yosemite. Has been great since I bought it in late 2008. All of a sudden, the computer shuts down and will not start up. It gets about 1/4 of the way through the progress bar and shuts down again. Same thing happens after several tries of restart. I don’t know what do at this point.
Can someone please help me?