Clean Install of Mountain Lion The Hard Way

It was supposed to be so easy. That's what the guide I used said. I've been having a few problems on my Mac with applications crashing and taking down OS X with it, so I decided to take the opportunity to download Mountain Lion and rebuild my iMac from scratch.

A quick surf around the web at lunchtime produced a great tutorial called How To Create A Bootable OS X Mountain Lion USB The Easy Way. Having read this it seemed pretty straight forward, so after getting home from work I set about following the instructions.

All went well until I had wiped my Mac internal hard drive and was beginning the install of Mountain Lion. It estimates 6 minutes until is needs a reboot, counts down to 0 minutes then sits there for about 5 further minutes. Then I hit an error message:

"Can't download additional components needed to install OS X"

Oh dear. Never mind, looks like my wireless network wasn't connected. Should fix it. So I re-run the "Reinstall OS X" menu option.

Same message.

I try this several times with the same, frustrating result. At this point I can hear my mates with PCs laughing at me, because Macs are meant to be easy. Right?

So I hit Google again and come across a forum post on MacRumours. Basically, this guy is having the same problem as me and there are a few answers but nothing really helpful to me.

There is a link to a guide on creating a bootable USB that doesn't need the download elements, but I have no OS X in which to do this. Those of you with a 2nd Mac should try this.

A bit more searching reveals a helpful MacWorld article on "Recovery Mode". If you have Lion, or Mountain Lion, installed before attempting a clean build a partition will be created to allow you to access components to rebuild the machine.

Using the cmd+R keys on startup I manage to enter this mode. I am authenticated using my Apple ID and I can begin recovery of Lion. But I want Mountain Lion. So I decide to try the USB one last time.

Still that same message.

So I reboot and hold down cmd+R. This time, I am taken to the Internet Recovery Mode. This I am supposed to get to using alt+cmd+R. Maybe I hit this by accident, but I decide I am taking no more chances. I am offered the chance to recover Lion and I take it. By the way, Internet Recovery Mode takes ages to enter - about 7 minutes on my Mac. So make a nice cup of tea. You will probably need it!

So I have gone with "Reinstall OS X" and I am now downloading Lion. This takes approximately 45 minutes on my Internet connection, but may be faster or slower on yours if you are at this point too...

The screen says "About 0 seconds remaining" for about 10 seconds then reboots. I am now greeted with a nice "Install Mac OS X" screen and an estimation of 23 minute until completion.

I am then greeted with a cheery reboot button. This doesn't reboot, however, but throws me back to the Mac OS X Utilities screen. So I reboot from there. Macs are intuitive, apparently :-).

Hurrah! A clean install of Lion!

So what now... Well, I still want Mountain Lion, so I go to the App Store and start the 4.37GB download AGAIN!!!

Meanwhile, I run Software Update to make sure I'm on the latest version of Lion. I read somewhere you need to be on a pretty high version to run the Mountain Lion upgrade, so best to check I am on the latest build. It turns out that the recovered Lion is the latest version, so I decide to download a few bits and pieces like a new Safari update and a malware removal tool.

Luckily I have a fast Internet connection, and also need another cup to tea....

40 minutes later and I have it downloaded. Not quite. 30 minutes in I have had the "restart computer" death message which I have been hoping to avoid that totally crashes my machine... I suspect my memory is bust, but that's another story...

Then I remember the Mountain Lion install program in on my memory stick. The one I tried to boot from. Doh! I can use that...

I decide to just upgrade Mountain Lion over Lion (after I have rebooted) and call it quits... I could try and do a really clean install of Mountain Lion by recovering it after I have upgraded the Lion, or creating another bootable USB, but I can't be bothered. Especially as my "restart computer of death" message seems to have nothing to do with the OS.

So off we go with the upgrade. I'm nervous as the screen looks the same as it did before. The preparing to install and 6 minutes remaining message appears, as before. This time, I am hoping it actually works... It still decides that there are random minutes remaining, flicking between 6 and 3 erratically, whilst the blue bar inches across the screen.

After 15 minutes of this - the old classic message appears about not being able to download components. Right - re-download from App Store then...

Another 40 minutes, and another cup of tea, move on by. I hope my Internet broadband provider aren't monitoring my connection too much tonight as I am getting through a lot of downloaded data!

I decide to copy the file over to a USB stick. That way, if it goes pear-shaped, I don't have to download it again. It's more delay, but I'm getting used to waiting...

That done I start the installer. I am met with the screen above. Uh-oh. But the good news is it only lasts for a few seconds before we are restarting the Mac and off to the Mountain Lion installer. Hurrah! Getting somewhere! It guesstimates 34 minutes to install....

After watching some tele, I'm back in front of the screen and we are done. It has taken about 30 minutes.

I don't know if this rant is helpful to anyone, but it felt good to document my trials anyway :-)

If I did this again, I would go into the Recovery partition and install Mountain Lion from there. If I were to give you advice on upgrading from Lion, I would probably install Mountain Lion through OS X, then head to the Recovery partition and clean install it from there. After you install Mountain Lion, the Recovery partition will allow a clean install of it, overwriting the previous Lion Recovery.