Flashing Question Mark on Start-up.
iMAC Intel 24" A1225 dispaly a flashing question mark on start up. I have read related problem with these here at ifixit. I tried reinstalling the MAC OS X using the system installation CD (10.6 and 10.6.3) but it would not continue booting on installation CD. I did this several times, replace the HDD with new HDD but still it dispaly the flashing question mark..i also replace the optical drive with working optic drive but still it display the flashing question mark..
can anyone encounter this problem before.. pls help.
Try the following:
1. Boot up holding down the option key. Can you see your internal drive as an option? How about the startup disk that came with your machine? If you have an external bootable drive connect that, can you see it? If you don't see any bootable systems while booting with the option key being held dow, then you've got a serious hardware problem.
2. Zap the PRAM by holding down the Option-Command-"P" and "R" keys- Probably won't help but you never know.
3. Can you boot up in target disk mode. Hold down the "T" key while booting up. You'll end up with a FireWire icon on the screen. If not serious hardware issue again.
4. Schedule a genius appointment at an Apple Store and get a quick evaluation by an expert.
Can't find a boot
disk (System folder). If you put in a new HDD you need to format it and install a system on it.
If that was done before the install then you've pooched the logic board, ribbon cable, or connector to the HDD. Only you know if you have fully connected the HD, only you can tell if damage to the connector, ribbon cable or logic board is more likely.
Remember to return and mark accepted the answer that best solves your problem.
I have sort of the same problem.
It started when the Imac went to sleep (with "put hard disk to sleep when possible" checked as a "energy saver" preference option") and I tried to wake it up... I would get the beach ball, and had to shut down using the power button.
For a while it would start right up again.
Now I get the flashing question mark when I try to start up.
So I was pulling the power plug, and waiting over 15 minutes before starting up with a pram zap, and then it would start.
But that also stopped working yesterday.
Now if I pull the plug and wait a few hours (sometimes overnight) and start up with a pram zap, it will usually start up.
I have turned off the "put hard drive to sleep when possible" option in Energy Saver preferences and it has been running for a few hours now.
I haven't shut down yet to see if it will restart, because I don't want to be without my computer till the new one gets here, and then I will decide if I should spend the money on a hard drive to see if that gets this IMac going - still a good machine, but now worth hundreds in repairs.
I had also reinitialized the drive and reinstalled the system software. That made no difference. Wiped it with the 7 times erase option - took 11 hours.
So, I am thinking it's a drive, but will probably try the memory trick also.
Glad to share
I use winxp for a while on iMac 24" then decided to upgrade to mountain lion so I restarted the iMac by pressing option key. Then flashing folder with question mark appeared. I tried everything option, c, shift, etc. nothings work so I gave up and left it for a night, came back in the morning it loaded up osx fine so I upgrade to mountain lion, fix hd permissions then restart the machine then flashing folder appeared again. I going to take my iMac 24" to the shop to get the hd replace but couldn't help myself thinking, if I didn't decide to upgrade the machine then it still runs fine.
Anyone knows what I did wrong?