Stuck at Gray Screen. Won't boot up!

[Raven]

I rebooted, the gray screen shows up and the gas bar stalls at about 40-50% full.

Not sure if this has anything to do with it…
All this started when I tried to import my photos from my iPhone 6 last evening. After an hour, it stalled at about 20%. There was a message on the iPhone screen "this device may not be supported". I've done this before and never had that message.  I'm using the iPhone cable to a USB2 port on a USB hub.

I then disconnected my iPhone and Repaired Permissions. Not sure if that would help.  Permissions were repaired, but one line said "… could not be repaired". So I thought I would Repair Disk. Tried to reboot from a new Start Up Disk (my EHD).

That's when all this started. I heard the loud chime, then gray screen and the gas bar stalled.
After two hours nothing has gone further. I powered down the power button at the back. I unplugged and replugged.
Tried it again with same stall.

What can I do? My Mac is my business!!  :-(

24" iMac. OSX10.10. 60% full HD.
2 External Hard Drives for Time Machine and Super Duper.

[Paddy]

Can you:

1. Boot into Safe mode? (Start up holding down the shift key)
2. Boot into Recovery mode? (Start up holding down the R key)
3. Boot using your Super Duper backup? (is this what you were trying to do?)

If you boot into recovery mode, you can run Disk Utility from there.

If you can boot into Safe Mode I'd try that first: https://support.apple.com/en-ca/HT201262

As for the iPhone thing - try connecting it without the hub. If that doesn't work, try a different cable if you can. And check to make sure the connector for the cable is clean.

[jchuzi]

I found OS X Yosemite: If you see a gray screen at startup but I don't think that it's very helpful. It says nothing about hard drive failure (which is a possibility in your case). See if any of the links at this Apple support page help.

[Paddy]

QUOTE(jchuzi @ Oct 27 2015, 12:45 PM) <{POST_SNAPBACK}>

I found OS X Yosemite: If you see a gray screen at startup but I don't think that it's very helpful. It says nothing about hard drive failure (which is a possibility in your case). See if any of the links at this Apple support page help.

As Jon notes, hard drive failure is definitely a possibility, but you need to rule out other possibilities with the various steps I've described above. If you have either TechTool or DiskWarrior, those can be run as well - either from your backup drive (assuming you've got them installed and assuming you can actually start up from your back up drive) or from a CD if you have a CD drive.

In addition to hard drive failure, it's also possible that there is some other mechanical/electrical issue. My son's girlfriend's MacBook Pro recently started behaving badly - somewhat similarly to what you're seeing. I suspected hard drive failure as we were able to get it to start from an external drive. So we got a new drive and my son installed it (yay...finally got him to learn to do that sort of stuff without handing it over to Mom!!) and still no joy. At that point I started wondering if it was a cable, since it would work from an external drive. Hoping of course, that it wasn't a logic board issue, as she has no spare cash and that's an expensive repair. They took it in and I was right - it was the hard drive cable. While not cheap ($169 for diagnosis and repair) it was a heck of a lot cheaper than a new logic board or a new Mac!!!

Next time I think I've got a dead drive on my hands I'll try to remember to test the darn thing in an external enclosure before jumping to conclusions. On the upside, she now has 2 backup drives - I made her buy one immediately and now she's got the old internal as well - one for TimeMachine and one for CCC.

[Raven]

PROBLEM SOLVED!  

After the 3rd attempt of rebooting and getting a frozen gray screen, I unplugged everything including 2 EHDs and the power cord. Rebooted without the EHDs. Everything started and has been running well. Plugged in the 2 EHDs again. Rebooted again today to test and all is COOL!!
Well, almost... I will post about a consistent glitch since I upgraded to 10.10 this summer. See my separate topic.

Thanks again all the good folks at TS!