Filed under: OS, Software, How-tos, Leopard
Leopard How-to: Clean install
Happy Leopard Day! Reader Zach wrote in asking us how to perform a "clean install" of Leopard and the best way to back-up programs/settings. Let's take a look. Before doing anything, make sure you read Mat's Guide to preparing for Leopard - there are some great tips about backing-up and preserving your program data.After backing up your system, insert your shiny OS X 10.5 DVD into your Mac and restart the computer, holding down C, so that the Mac boots off of the DVD-ROM.
After a few moments, you will be presented with a Leopard installation screen and presented with a number of options (some options may not appear on all systems, depending on model, previous OS version, etc.).
Upgrade to Mac OS X - this option will be fine for most users who are migrating from 10.4.10 and do not want to reinstall programs/personal data. If you are buying a new Mac that comes with the Leopard Upgrade pack-in - this will be the most hassle free choice.
Install Mac OS X - this is the option for anyone who either a) does not have another version of OS X on their system (new hard drive) or b) wants to do a new installation.
Under Install Mac OS X - there are several options:
Archive and Install
This option will archive the current contents of your system folder and install a new copy of Leopard. By default, your network settings (WPA or WEP passwords, VPN settings, etc.), user accounts and Home folders will be re-imported into Leopard. While third-party programs will be left intact, Apple still recommends that you reinstall them to ensure good working order.
Personally, Archive and Install isn't a bad idea - but if you already have up to date system back-ups anyway, and since you are going to have to reinstall most of your software, I say skip this step and just go for the second option, the option Zach asked about:
Erase and Install
This will erase the contents of your drive, format it into HFS+ and install Leopard clean. EVERYTHING ON YOUR HARD DRIVE WILL BE ERASED. If you choose this option, it is crucial that you back-up all of your data safely before the installation. If you select this option, you can click on an "Options" button that will give you additional choices, for instance, removing language files you may never use -- but if choices make you uncomfortable, just go for the standard installation.
After installing Leopard - whichever method you choose - it's time to re-import your data - using Migration Assistant, per Mat's guide.
Update: A lot of people in the comments are asking about boot camp updates -- unless you specifically use Disk Utility to delete or change your partitions, just installing on your set Tiger partition should leave your Boot Camp sector untouched. I'm not sure what changes were made in Boot Camp in Leopard from the beta - so you may end up having to reinstall or re-setup that partition. My Boot Camp partition was actually on another drive (using a cooked XP install with USB boot support enabled), so I don't know for sure.
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Reader Comments (Page 1 of 2)
Jamie Parsons said 10:46AM on 10-26-2007
Software Update still not working for Leopard!
Problems with my iMac too! :(
any idea how to get wireless keyboard to work on start up?
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Jamie Parsons said 10:40AM on 10-26-2007
Software Update still not working for Leopard!
Problems with my iMac too! :(
any idea how to get wireless keyboard to work on start up?
Reply
Adam Yellin said 10:54AM on 10-26-2007
FIRST!!
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unteins said 12:31PM on 10-26-2007
Is there any reason not to use the built in Disk Utility to image the hard drive and then do a clean install?
Other than say, needing an external drive the same size as the original.
And is there a difference between doing an upgrade install and doing a clean install and using migration assistant (what exactly does Migration Assistant do to Migrate Applications and data, where you might get a lot of cruftiness.
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mungler said 11:00AM on 10-26-2007
FOURTH!
lol @ adam
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Jerry said 11:07AM on 10-26-2007
I have installed Leopard, and didn't see the options mentioned in this post. Instead, when I popped in the DVD and double clicked Install Leopard in my 10.4 install, it rebooted and proceeded to do an upgrade. I had the problems described in the following link with the blue screen after upgrade that just hung out there.
http://itsallmac.com/blog/2007/10/26/oh-no-leopard-problems/
So I had to reinstall - I run the disk again and don't see the options to do an erase and install. Instead, I have to use disk utility to blow away my hard drive first. I was still having problems wiping the drive, and had to delete the bootcamp partition first, then wipe the rest of the drive. I think this bug might be related to the bootcamp betas. Thank goodness I had a SuperDuper backup, and I migrated my data at the end of the install. All running now.
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WR said 11:10AM on 10-26-2007
Trying to upgrade to leopard but after installation computer stucks on a blue screen and nothing happens. Rebooting doesn't help. Remind me of my windows times. Now I'm having non working computer with leopard in it. Even Apple support don't have any answers.
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Chris G. said 11:16AM on 10-26-2007
Question. I did a full backup with SuperDuper! to my external USB 2.0 HD.
Do I have to worry about any file permissions or that stuff? I am worried that when I do a clean install of Leopard that I won't be able to access my wife and I's user folders that were backed up to the external HD.
I didn't turn on FileVault, so that isn't an issue. I am just worried about the default permissions OS X assigns user folders.
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David said 11:38AM on 10-26-2007
Any verdict on how a clean install affects the boot camp partition??
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Ben said 11:23AM on 10-26-2007
You say it deletes everything on your drive, but do you mean the HFS+ partition, or will it actually erase your bootcamp partition too?
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jus10 said 11:27AM on 10-26-2007
So based on what I'm reading, upgrades are blowing up. I was going to go with the Erase and Install method myself but it is good to know that I can't do the double click from inside of Tiger to do that. I'll do the hold C, boot, erase and install method.
Of course I'm at work with Leopard and my Mac is at home so it'll be a few more hours.
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Matt Norris said 11:30AM on 10-26-2007
Chris G.
Super Duper is smart in that it should have repaired your permissions for you. Make sure you have that optioned checked when doing a super duper backup, but as long as it was checked you should be fine.
Matt
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jus10 said 11:33AM on 10-26-2007
@ 7 Chris G.
Well, even if the owners change (ie, you create a new user in leopard and that user's UID is different from what it used to be in Tiger) you should still be able to use sudo chown to change the owner back. As root you should be able to access every file on the system (unless they're encrypted which you said they weren't).
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Jerry said 11:34AM on 10-26-2007
Just to be clear, I didn't have a problem with boot camp per se, all my problems were with Leopard itself and having the blue screen hang during startup after the grey apple/circle screen.
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iGO said 11:52AM on 10-26-2007
Ooooohh!!!....I have received my Leopard product but I will NOT do any install for at least a week or two.....I want to see how all this plays out in the Apple community before I choose to be a guinea pig....Keep the feedback coming, me eager rodents and Thank you! for all your efforts
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cozart said 11:55AM on 10-26-2007
so over at SuperDuper they say that the program is not Leopard compatible.
does this mean that back-ups and settings created in Tiger will not be able to be restored after the upgrade to Leopard??
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Jerry said 12:05PM on 10-26-2007
cozart,
No that means you won't be able to take new backups in Leopard once you upgrade. If you want to restore to Tiger, you can boot off of your SuperDuper backup and restore to the main drive. Also, this has no impact on retaining your settings, or even migrating your settings off of your backup.
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kirk said 12:21PM on 10-26-2007
How well does Migration Assistant work after doing a clean install?
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Jerry said 12:40PM on 10-26-2007
Migration Assistant worked very well for me and allowed me to recover from the Blue Screen problem (see above). All of my applications and data transfered over - I see migration assistant as an upgrade, with the files coming off of an external drive (or other mac) rather than having Leopard install around them on the main drive. To me, it appears, both an upgrade and migration assistant achieve the same exact state of your final install. One caveat: migration assistant allows you flexibility in what you copy over, where an upgrade doesn't (obviously). For example you can copy over the user directory, but not the applications folder.
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Alan said 12:41PM on 10-26-2007
Why would I want to do a clean install? What are the benefits?
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