iMac won't turn on. Only a clicking sound and a grey folder with flashing question mark.
Your iMac is actually turning ON as proven by the grey folder with the flashing question mark.
The flashing question mark indicates that your system is unable to find a bootable volume. The clicking sound that you hear is probably coming from your hard drive while it tries to recalibrate. I suspect your hard drive has failed.
What model imac do you have? If it's under warranty I suggest taking it in for service. Hopefully you've been maintaining a regular backup of your data as all users should. I lost my data once and it was a valuable lesson. I back up regularily now.
If your iMac came with install disks then you can boot from them, choose your language when asked, then pull down the Utilities menu to launch the Disk Utility application. The Disk Utility application will allow you to verify whether your hard drive has an issue. Usually a clicking sound, assuming it's coming from the hard drive, is a sign of a bad hard drive.
If your system has Lion installed then you can hold down the Command and R keys when you restart the system, then launch the Disk Utility application from the menu that appears.
In short your system has had a HD crash and the HD needs to be replaced, if the machine is covered by AppleCare call them today and they will help arrange getting it fixed. The phone number is in your owners manual or you can use the AppleCare Contact Info link to find it. If your machine is not covered by AppleCare then make an appointment at your local Apple Store or AASP to have it professionaly diagnosed and have the HD replaced. If you have been backing up then restoring from the backup will be quite easy. Let the Apple Store or AASP know you have backup and they should be able to help you restore. If you have not been backing up then you will soon find out why this is the single most important thing you should do to preserve your data on any computer.
You can re-download Lion from the Mac App Store if you have already paid for it. Please look over
for instructions on how to re-download Lion.
If you would like more information about the condition of your hard drive I suggest downloading a copy of SMART Utility. The application pulls the SMART (Self-Monitoring,, Analysis, and Reporting Technology) logging files that are maintained by most major hard drives. If will tell you a great deal about the number of errors your hard drive has encountered. It may be helpful info for the service provider you go to. You can use the application in the demo mode to gather this information.
I got the same problem,white screen with grey folder sign and question mark!!!! Is there any way I can fix it at home?????
Please carefully read Flashing question mark appears when you start your Mac for trouble shooting instructions.
Also please begin your own thread, while you may have similar symptoms the cause be be completely different.
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