Updating to a newer version of mac os x
Don’t worry about getting things like Mail or i Tunes set up again yet, though.
Just make sure to do things like get connected to your wireless network, get your mouse/trackpad settings back the way you like them, set up your printer again, etc.
At this point, you can manually copy your user data from the clone backup back into your new user folder.
Don’t try to copy any settings files – nothing from your Library folder, for example – just documents.
For other apps, you may need to search for instructions on where to find the data and preference files.
At this point, you can start reinstalling any other applications you might have had installed. Reinstall them from the original disks, or download them from the original source.
Select “Mac OS Extended (Journaled)” from the Format pop-up, if that’s not already chosen, then click the Erase button.
Hold down the ‘c’ key as soon as you hear the chime, then let go when you see the Apple logo.
If you do, and one of those applications was causing the problem, you’ll never know which one it was and you’ll be back at square one, with a lot of time wasted.
Install third-party applications one at a time, with a period of testing afterward to be sure the problem doesn’t come back.
If you are reinstalling Lion (Mac OS X 10.7) or later, restart the computer and hold command-R as soon as you hear the chime. Note that when you begin the install process, you will need to download about 4 GB of data, so be sure your internet connection can handle that before proceeding.
Once in Disk Utility, you need to select your hard drive in the list and select the Erase tab.