How can I install Mountain Lion from the Recovery disk of a machine that had Lion ?

if you already purchased Mountain Lion - then it's legal for you to install it in your macbook.

You can create a Mountain Lion USB installer.

Click here on how to create on so you can install it in your 2009 Macbook.

You'll need a 8GB USB Thumb Drive to create a bootable installer.

Good luck..

Hello GEE_OTTO, welcome to & thanks for using the Apple Discussions,

I'm not sure I understand fully so I'm going to write what I understand your situation to be:

You wrote "MacBook (Uni-body Aluminum 2009 MacBook..)" - the aluminium MacBook was late 2008 (MacBook 5,1) or do you mean 13" the MacBook Pro late 2009 (MacBook Pro 5,5)?

In either case as I understand it you perfeormed an OS recovery using the Lion Recovery System. This downloaded & reinstalled OS 10.7.x on your system. If that's the case & you've purchased OS 10.8 Mountain Lion off the Mac AppStore then you should be able to download and install that.

If my above understanding is correct & you can perform a Mountain Lion install I'd encourage you to go ahead. Once you do the installater partition should be updated to the Mountain Lion Recovery System. See this support article for more on the Lion & Mountain Lion Recovery System:

http://support.apple.com/kb/HT4718

This article also will show you some info on how to install a bootable copy of 10.8 to an external device (like a USB drive). That may not be exactly what you're looking for so if you'd like to use a USB device like the Recovery System (which is to purely install 10.8) check out Lion DiskMaker which automates a majority of the process:

http://blog.gete.net/lion-diskmaker-us/

Let us know how this works out for you, GEE_OTTO!

mac.heretic wrote:

You wrote "MacBook (Uni-body Aluminum 2009 MacBook..)" - the aluminium MacBook was late 2008 (MacBook 5,1) or do you mean 13" the MacBook Pro late 2009 (MacBook Pro 5,5)?

Macbook Uni was offered in 2008 - 5.1 and in 2009 - 6.1....

You are however, right - it could also be a late 2009 Macbook Pro....

<redacted>

You are correct - my mistake...cheers..

<redacted>

just edited it....cheers..

i can accept when i've made a mistake - it's all good...

My first link will install the entire OS to the USB drive, so if you boot from there you'll be in a fully operating Mountain Lion environment.

The second link (to Lion DiskMaker) may be more of what you're looking for which is to create a recovery partition on the USB drive that you can use to reimage the system should your HDD fail & you not be able to load the Mountain Lion Recovery System.

Noo problem Gee, glad to help. That's why we're here. 🙂