Some you can copy back on, others will kick off the moment you open them up; typically asking for a serial number.
Always do an audit on your system, go through all of your applications to determine what you need and what you don't:
Preferences & Settings
- Be sure to go through all of your preferences in the System Preferences application. This is the biggest single cause of frustration when updating your computer. Be thorough and go through every preference pane and copy out _all_ of the settings and then write them down on paper.
- Go through your favourite applications and make a note of certain settings. With applications like Address Book, you can even export all of the card data.
- If like me, you have over 8 gigabytes of music in iTunes, you have a problem. So you need to be sure you have an external hard drive large enough to store all of your temporary stuff, like applications, games, presentation materials et cetera.
Passwords & Registrations
- No doubt you have username & passwords stored on your computer. These can be for anything from web site log-in sessions to certain software on your computer.
- Also, if you have commercial software on your computer, then you may very well have had to enter a serial code at some point. Sometimes, these registration details will not carry across since the software often deposits registration details in some obscure and often hidden file.
Internet & Mail
- If you're using Mail, then you need to go to your Home folder -> Library -> Mail and then back this up. Then, Preferences -> com.apple.mail.plist and back this file up, also.
- If you're using Safari, then you need to go your Home folder -> Library -> Safari and then back this up. Then, Preferences -> com.apple.Safari.plist and back this file up, also.
- If you're using Address Book, then you need to go your Home folder -> Library -> Application Support -> Address Book and then back this up. Then, Preferences -> com.apple.AddressBook.plist and back this file up, also.
- The above rules will pretty much apply for most other OS X-savvy software. The best thing to do may be to just back up your entire Library folder, as I did, rather than in a piecemeal fashion.
Work & Documents
- Should go without saying, but be sure to back up all of your private and personal stuff. How many times do we think: 'but I backed that up last week!' and then realise that the day after the back up you made a major change .. we've all been there!