Here i am going to give you some tips to fix the White Screen of death on your iMac which is called White Screen commonly. I would suggest you start using a program to create a restorable back up of your Hard drive to an External Drive. There were several free program like carbon copy cloner and It will make a mirrored copy of your hard drive in it’s current state that you can go back to if things go south for any reason. You do this personally before you perform any kind of install, update or major change to your system.
RESETTING THE PRAM
Turn the computer on, Then press and hold Command (has an apple on it),option ( sometimes called alt), P and R key before the gray screen appears. Hold these keys down until you hear the startup sound a total of 3 times. Release the keys. This resets the PRAM on the machine. If this works, then you would run Backup program and back it up before going any further. If it didn’t work, read on…
we need another mac to access with your mac. if you have now would be a good time to try to connect the two machines in Firewire transfer mode, that way you can at least get your important stuff off of the machine if it is able to boot up into Target Mode. If you do have another mac close and a Firewire cable to connect the two. You would try this first.
1. Shut down your troubled mac.
2. Start up the good mac.
3. Connect a Firewire cable between the 2 machines.
4. Press and hold the T button and then power up the troubled mac. Don’t let go of the T until the Firewire logo starts bouncing around on the screen.
5. This should connect the troubled mac to the good mac as an external hard drive.
6. You should then be able to backup the troubled mac to another external drive or to the good mac via Backup program (Carbon Copy Cloner)
If you don’t have access to another mac or the Transfer mode startup didn’t work, then try the following:
a) FORCE STARTUP FROM YOUR SYSTEM FOLDER:
Hold the “X” key during startup. This may force the computer to start up to Mac OS X. If it does, open System Preferences and be sure that your Mac OS X System Folder is selected. If this works, restart after you have your startup volume selected. If this corrected the problem, STOP HERE. If not, go on to the next step…
b) BOOT FROM THE STARTUP MANAGER
Restart while holding down the Option key. This should bring up the Startup Manager and would allow you to select the startup volume. May work, if the computer is stuck and can’t find the correct startup volume. If this works, open System Preferences and be sure that your Mac OS X System Folder is selected. Restart after you have your startup volume selected. If this corrected the problem, STOP HERE. If not, go on to the next steps…
1) Unplug everything (ipod, usb hard drive, printer, etc) except the mouse and keyboard from the computer. Then restart. Does the machine boot up or get stuck again? If it starts up, plug each thing back in one at a time, restarting the machine each time until it locks up. Remove this item and continue adding items until you have everything plugged back in that you can and still have the machine restart successfully.
2) Plug everything back in (but make a note of what caused problems for later troubleshooting). Start up the computer in safe boot mode. To do this, press the power button. As soon as you hear the startup sound (immediately after you hear the sound, but not before), press and hold the Shift button. Let go of the Shift key as soon as you see the gray apple icon and the progress bar (or wheel). Does the machine boot up or get stuck again?
3) Insert the Mac OS X install disk. Start the machine while holding the C key. If you have to choose, select the Installation disk as the startup. When it starts, cancel the Installation process. Then go to the Go menu, down to Utilities. Choose Disk Utilitties. Run Disk Utilities and “Verify” the Hard Drive. Repair any errors that it may find. When finished, restart the computer normally. Does the machine boot up or get stuck again?
4) Let’s try to reset the PRAM again at this point. turn the computer on then press and hold command,option (sometimes called alt), P and R keys before the gray screen appears. hold these keys down until you hear the startup sound a total of three times. Release these keys. If it is booting of at this point then go to the next step.
5) Before any Application are running, go to Applications/Utilities/and run Disk Utilities. Verify, Repair & Disk Permissions problems that the program finds.
6) Restart Normally.
I hope this helped to remove White Screen of Death on your iMac, if you are still having problems then please post comment below. Let’s troubleshoot together.