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Doing a Clean Mountain Lion Reinstall: Putting the Vroom Vroom Back in My MacBook Pro

Activity Monitor on MacBook Pro

That probably looks like a heck of a boring screenshot up at the top of this post, but to me it’s a sight for sore eyes. It’s a shot of Activity Monitor’s CPU section on my MacBook Pro today – showing a little above 92% CPU idle %age and the MacBook Pro barely breaking a sweat while running all my essential daily apps.

In other words, the MacBook Pro is kicking ass and taking process names just like it should be – but it hadn’t been doing for quite a few months. In fact for a number of months the MBP was just running like a dog quite often. I’d been doing bits and pieces of maintenance and optimization on it for a while, trying my best to stave off having to rebuild it. I’d trimmed a number of apps that weren’t essential, freed up tons of hard drive space (took it from just 15% free to 180GB free on a 320GB drive, and created a brand new user account.

I’d even made a couple of visits to the Genius bar at my local Apple store – where their geniuses ruled out any hardware or disk issues and did their best to do some trimming and optimizing as well. All these efforts had little or only very short-term positive effect.

Once I upgraded to Mountain Lion things just got drastically worse. That goofy spinning beach ball became a near constant companion, even when doing simple tasks like closing out of apps. Spontaneous logouts and reboots started happening every few days or sometimes more often. My keyboard would completely stop functioning out of the blue. And one graphics app in particular,Pixelmator, would crash easily half a dozen times per day.

A couple of weeks ago on a fine Friday  I got past my laziness and did a clean reinstall of Mountain Lion. And nearly two weeks later the MBP has got its mojo back, big time. It feels almost as fast and smooth to work with as when I first got it two and a half years ago.

So I thought it might be worthwhile to share my experience a little, just in case any of you are going through any similar sort of troubles with a Mac.

For starters I should mention that my MacBook Pro is a 15 inch mid-2010 model, upgraded to 8GB of RAM from a 3rd party vendor. I use it primarily for writing and working with images that will end up in post and keeping up with the latest news and social networks that I enjoy – so my staple of everyday apps includes a mail app, the Chrome browser (generally with somewhere around 20 tabs open), Parallels Desktop running a Windows 7 virtual machine, Tweetbot, Evernote, iA Write, OmniFocus, and a few others.

Here’s the rough rundown of how I approached my clean reinstall:

The Plan: My plan wasn’t complicated or complex. I just wanted to try for a clean, fresh install of Mountain Lion that would hopefully wipe out all my legacy issues. I decided I would not even reinstall apps, but would install them all fresh from the Mac App Store or the web – even though I knew this would be a pain because of the need to re-enter license information and to get each app setup just the way I like again.

Preparation: To prepare for the clean install I did things like:

— Checked on my Time Machine backup drive and tested a few small restores – verified all looked good.

— Manually backed up some essential files and folders to Dropbox and to a couple of external drives.

** Whatever way you choose to go about it, obviously backup of your essential data is critical before attempting an install or reinstall of any operating system.

— Took a snapshot of my Windows 7 virtual machine in Parallels Desktop.

— Found license info for my most frequently used apps and got it all together in an Evernote file.

— My iTunes library had already been moved to an external drive some months back, so I didn’t worry about it much.

— Did a fair amount of reading on the best ways to do a Mountain Lion clean install.

— Bought a 16GB flash drive to use as a bootable drive during the reinstall.

— Downloaded a recommended free app called Lion Diskmaker – recommended in this guide on Mountain Lion reinstall:http://osxdaily.com/2012/07/25/create-os-x-mountain-lion-boot-dvd-usb-drive-liondiskmaker/. It’s a great little app. Once you download Mountain Lion, you run it and it recognizes where the installer files are, let’s you select to create boot DVD or flash drive and fires away after just a few clicks. It even has a Homer Simpson WhooHoo sound as the alert that it finished creating a boot disk.

The Install Process: I used this easy to follow step-by-step guide: http://osxdaily.com/2012/07/25/how-to-clean-install-os-x-mountain-lion/

The install went smoothly for me, like most installs the worst part was just waiting while it happens. When it was finished the MBP rebooted far more quickly than it had been doing and seemed faster right out of the gate.

One Odd Issue I Encountered: When I started reinstalling apps I came across one strange issue with any that I had bought in the Mac App Store. Basically, despite having just wiped my MBP’s hard drive and done a fresh install, the Mac App Store (MAS)  insisted that apps were already installed. As in, in the Purchased section of the MAS it showed their status as ‘Installed’ – even thought I could look at the /Applications folder and see that they physically were not there, of course after the clean install.

A bit of Spotlight searching showed me what the problem was. The MAS was seeing copies of those applications in old backup directories on an external drive. The drive in question is not even my Time Machine drive – just a sort of ‘spare’ drive where I chuck miscellaneous backups that don’t fit elsewhere. As soon as I deleted each app out of the /Applications folder on that external drive, then the MAS would show the option to install it and I could successfully install it on the MBP hard drive.

This seems a bit bizarre to me that the MAS searches external drives, without being asked to, and won’t allow an install on the primary boot drive of the OS because of what it finds on external drives. Once I saw what was up, this was easy to fix by just deleting the apps on the external drive.

Anyway, the end result of the clean install has been superb. My MBP runs like a champ again and I’ve only had one other issue since the fresh start. The Pixelmator app continued to crash, lock up, and cause all sorts of hassle. So I found a replacement for it – a very capable and rock solid one that I’ll talk about in another post.

One thing I hadn’t even thought about until today is that Activity Monitor is no longer in my dock on the MBP, and I don’t miss it at all – because there’s nothing much to monitor.

How has Mountain Lion performed for you on your Macs? Have you got any tips to share on doing a reinstall?

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  • I think I’m going to have to do the same thing. Since upgrading from SL to ML, pretty much *any* activity is followed by several seconds of thinking time (with optional beachball) before anything actually occurs. Your article has given me hope that my MBP can regain its pre-ML zippiness, though reinstalling everything is going to be a right pain.