Thanks for that great guide! I would like to use it but I don't know if my Windows XP installation that I set up with Boot Camp of Snow Leopard would survive a clean installation from scratch. Do you know that?
It should. Then again, if you resize your Macintosh HD partition, you screw the pooch on your Windows install. For example, I resized my Macintosh HD last week, and ignored my Mac's warning saying I might loose Windows. Sure enough, I screwed the pooch. I cannot boot into Windows. Reinstalling the OS? I don't know if it'd survive a install of OS X. I would say try it, but what if it does go wrong? Then you would've screwed the pooch too, and it'd be my fault for saying go ahead. Anyways, I wouldn't recommend it unless you have a full image backup of your Boot Camp partition. Did you have this issue when migrating from Leopard to Snow Leopard, or no?
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Do I need to deauthorize my iMac in iTunes before I do a clean install (not just update)? Or will Apple "know" that my iMac is still the same?
Don't bother de-authorizing. Apple always knows that my Mac is well, my Mac. Even if it has a fresh install, it'll stay authorized.
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Great guide! Requesting sticky.
Anyway, this is my first time reinstalling a clean OS on Mac, although I've been doing it for years on Windows. Anyway, what content, other than iPhoto (photos) and some settings from iTunes (podcast subs.) should I backup? When all my content is stored either in Dropbox or on central server. Anything else one should normally remember?
Also: Can I get 100% confirmation that the ML installation WILL NOT fit on a 4 GB mem stick? Since I've got many of them and none 8GB.
What should you backup? Your entire machine. I'm not even kidding. I wouldn't rely on Dropbox with a system's-worth of data. I don't believe it'll fit on a 4GB USB flash drive. I think it might, I'm not sure. Disk Utility will tell you as soon as you click restore if it'll work or no. It might, I don't remember.
Oh, and thank you for requesting sticky.
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First, thanks for putting this together. I appreciate the work put into it.
Second, if I could make a suggestion (and I've seen similar instructions make a similar mistake), why would you make a backup and THEN check for updates? I think the sequence of events should be to check for all updates THEN make your backups. At least, that's what I would do.
That's what I would do, too. However, I'm excluding any new system updates from this Time Machine backup, because some people don't want to install all the new system updates. Plus, there have been cases where a simple system update can ruin a machine, and then you'd backup that ruined system to your backup disk, ruining your perfectly fine backup. If you want to reverse the steps, go right ahead. Just proceed at your own risk.
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I know this is silly but would an SD card in a USB SD card reader work fine for installing Mountain Lion? I have a bunch of 4GB USB sticks but none of them can hold more than 4GB. I have loads of 8 and 16 GB SD cards though
I'm not going to buy a USB stick just for a hopefully one-time installation, no matter how cheap it is. This is when I realize that no proper replacement for CDs and DVDs was ever invented.
I just looked it up, and according to The Unofficial Apple Weblog, it is possible.