How to Properly Migrate With a Clean Install to OS X Mountain Lion (From Lion/SL)

[njaremka]

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.

[Paulyboy]

Thanks for doing this. Very useful! :-)

-PN

[macklos]

I would highly suggest creating a bootable backup of the system drive using carbon copy cloner/super duper. Don't rely on Time Machine alone.

Test the clone before wiping the system!

Also Lion Disk Maker is an easy way to create a USB/SD OS installer.

[TexasChemE]

This is a great guide. Thanks a lot for doing this!

[keaide]

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?

[chiefroastbeef]

Thank you William for this guide!

I am still on SL (10.6.8), and decided not to upgrade to Lion because I didn't feel like reinstalling all my apps (Final Cut Studio, Adobe Suite, some web dev apps, and many plugins...). Now that ML is coming out, I would like to make the upgrade, and your tutorial of now carrying over App settings is worth a try.

From all the things I have read, 10.6.8 should upgrade to Mountain Lion.

Do you think I can follow the same instructions upgrading from Snow Leopard?

[indycolts2k6]

First, I just want to say a big "thank you!" to the author of this thread and documentation - this was exactly what I was looking for.

My first Mac was in 2009 so I guess I'm still a bit of an Apple newb and I really want to do a fresh install of Mountain Lion, just because my Macbook Pro is getting a bit slow and I can tell it's time. I'm a little scared of doing this, just because I've never done it on a Mac, but I'll be following these instructions step-by-step.

Quick question though - I have a 2011 iMac at work and heavily rely on a Parallels VM running Windows 7 for all the PC-only software I have to run - if I do a Time Machine backup will I be able to easily restore my Parallels VM?

Thanks again!

[Steve.P.JobsFan]

OS X Mountain Lion will be released in a few short hours for those of us in the United States and Canada. I was hoping to spend a day exploring ML, but I'm in Pittsburgh, Pennsylvania with my PowerBook G4, and forgot my IP of my iMac to remote in, and begin downloading Mountain Lion to it. I probably won't be on it until late tonight.


Anyways....


MODS PLEASE, PLEASE, PLEASE STICKY THIS THREAD! I, AND MANY OTHERS WOULD APPRECIATE IT! THANK YOU!


PLEASE LET ME KNOW HOW THIS GUIDE WORKS OUT FOR YOU, AND IF YOU ARE ABLE TO DO A CLEAN INSTALL OF OS X MOUNTAIN LION. IF YOU HAVE ANY ISSUES, DO NOT HESITATE TO CONTACT ME. I WILL WORK AS QUICK AS POSSIBLE TO RESOLVE ANY ISSUES.

----------

Originally Posted by indycolts2k6

First, I just want to say a big "thank you!" to the author of this thread and documentation - this was exactly what I was looking for.

My first Mac was in 2009 so I guess I'm still a bit of an Apple newb and I really want to do a fresh install of Mountain Lion, just because my Macbook Pro is getting a bit slow and I can tell it's time. I'm a little scared of doing this, just because I've never done it on a Mac, but I'll be following these instructions step-by-step.

Quick question though - I have a 2011 iMac at work and heavily rely on a Parallels VM running Windows 7 for all the PC-only software I have to run - if I do a Time Machine backup will I be able to easily restore my Parallels VM?

Thanks again!

Should work fine. Just make sure nothing is in the "excluded" list of Time Machine. Since we're doing an entire system backup, it should backup the app itself, the settings, and the actual image file of your virtual machine.


This would be the time for me to make a disclaimer. I am not responsible for any damages to data, or your computer. I am working of previous knowledge of how to clean install with OS X Lion. Since they're distributing OS X Mountain Lion the same as OS X Lion, instructions should be the same. Just make sure you have data backups, in the unlikely event something does go wrong!

[eNJayBe]

Hello,

would this work with using a DVD instead of a USB flash drive?

I've got some spare 4.7GB DVDs but only a 1GB flash drive so I'd need to go out and buy a new USB flash drive. If I did would a 4GB USB drive be big enough or is it safer to get an 8GB?

Thanks

Nick

[Steve.P.JobsFan]

Originally Posted by eNJayBe

Hello,

would this work with using a DVD instead of a USB flash drive?

I've got some spare 4.7GB DVDs but only a 1GB flash drive so I'd need to go out and buy a new USB flash drive. If I did would a 4GB USB drive be big enough or is it safer to get an 8GB?

Thanks

Nick

It's safer to get an 8GB USB flash drive. That reminds me, I need another flash drive. I used my 8GB one for OS X Lion. Thanks for the unintended reminder!

[adztaylor]

Think I saw somewhere that ML won't fit on a single layer 4.7GB DVD. Need a dual layer DVD if your gonna go that route. Which is what I'll be doing if I decide to clean install as I don't have a big enough USB stick but plenty of dual layer DVDs.

[baryon]

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.

[PaulKemp]

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.

[keaide]

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?

[WarrenFields]

Very nice guide! Thanks for posting.

[Steve.P.JobsFan]

Originally Posted by keaide

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?

----------

Originally Posted by keaide

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.

----------

Originally Posted by PaulKemp

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.

----------

Originally Posted by njaremka

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.

----------

Originally Posted by baryon

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.

[keaide]

Originally Posted by Steve.P.JobsFan

Did you have this issue when migrating from Leopard to Snow Leopard, or no?[COLOR="#808080"]

My first MacOS was Snow Leopard. I did a normal update to Lion last time. No problems back then. So this is going to be my first "fresh" install. I have 2 time machine backups and a backup of all my Windows content. But didn't find a free Mac app to actually clone the bootcamp partition yet. So some residual risk remains.

And thanks for your reply regarding my iTunes question.

[Steve.P.JobsFan]

OS X Mountain Lion is officially out in the United States and Canadian Mac App Stores! Go, download it! While I feel like an idiot for forgetting to turn on VNC on my iMac before I left the state....

[mateus]

Excuse my ignorance, but can you not just install ML from the app store and then boot into Recovery mode to do a clean install? Or would this just take too long.

[PaulKemp]

Originally Posted by Steve.P.JobsFan

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.

No worries in regards to the machine. In fact I know I will lose everything. That's why I'm doing a clean install. Dropbox is only for pics and documents. And a copy is saved on every machine I own.

And, yes, I can confirm that 4.7 GB it doesnt fit on a 4 GB USB stick.

----------

Originally Posted by mateus

Excuse my ignorance, but can you not just install ML from the app store and then boot into Recovery mode to do a clean install? Or would this just take too long.

I dont think the whole OS is stored locally, then you would have to download it again while in Recovery. I'm using ML GM and testing now, even with a super speedy internet connection it takes some time to just launch the OS X Utilities.

EDIT: In fact, when using ML GM and booting into Recovery, I only had the option to re install Lion. (- the mountain). Interesting. And this machine was shipped with SL. However, this could be different if the OS was installed via the App Store as I did with Lion. Will have to confirm this later today.

[ATC]

Thanks OP for the guide. I just tried it with ML and at the 9th step on page 2 (restoring to the flash drive) I get this error:



FWIW, the drive is 8GB but even after erasing it's showing a used portion (under the partition tab in Disk Utility). No idea how to fix that. It shows as empty in finder though.

[yaymath]

I'm downloading Mountain Lion and it's 4.34 GB. Isn't the capacity of a single-layer DVD 4.38 GB? If so, it should fit, shouldn't it?

[Steve.P.JobsFan]

Originally Posted by ATC

Thanks OP for the guide. I just tried it with ML and at the 9th step on page 2 (restoring to the flash drive) I get this error:

Image

FWIW, the drive is 8GB but even after erasing it's showing a used portion (under the partition tab in Disk Utility). No idea how to fix that. It shows as empty in finder though.

Click on the partition named "Mac OS X Install" and click unmount in the toolbar. Then try restoring the image again.

----------

Originally Posted by yaymath

I'm downloading Mountain Lion and it's 4.34 GB. Isn't the capacity of a single-layer DVD 4.38 GB? If so, it should fit, shouldn't it?

The capacity of a single-layer DVD is 4.7 GB. It should work, but sometimes it doesn't always work that way. The only way to find out, it to try it.

[yaymath]

Originally Posted by Steve.P.JobsFan

The capacity of a single-layer DVD is 4.7 GB. It should work, but sometimes it doesn't always work that way. The only way to find out, it to try it.

4.7 GB in decimal system, 4.38 in binary. So, you can't put more than 4.38 GB of stuff on it. Anyway, I hope that 10.8 fits.

[ATC]

Originally Posted by Steve.P.JobsFan

Click on the partition named "Mac OS X Install" and click unmount in the toolbar. Then try restoring the image again.

Hmm.. Still getting the same error.

I went and tried another method using the same flash drive (link in 1st post in this thread), which I think is the same thing it's just a script and it seems to work fine now. No idea what the problem was.