HowTo revert new MacBook Pro, Mac Pro or iMac to Snow Leopard

@tmcbride67

I found some candidates for enabling the trackpad under 10.6.7 using 10.6.8 drivers. Anyone else reading this should not experiment with this unless you are comfortable with terminal or willing to render your system unbootable. As such, you should only really try this on a test install because recovering from a kernel panic, while doable, is beyond the scope of this discussion 😉

So @tmcbride67when I look in my /System/Library/Extensions of my 10.6.8 install and sort by date, I see some kexts that were modified June 7th 2011 at the top level. The one that seems most promising is "AppleMultitouchDriver.kext."

As I look through the other kexts I saw some other potentially relevant ones. Some that were dated from 2009 had sub-kexts inside them that were dated from June 7th 2011 as well. I see:

[watch my spelling! These are not exact!]

AppleUSBMultitouch

AppleUSBTopcase

AppleBluetoothMultitouch.kext

AppleHIDKeyboard

AppleHIDMouse

The reason I include USB ones is because when I use System Profiler to look at the USB bus, the trackpad (and bluetooth) seems to come off the USB bus.

Still, at first, I would consider trying only the AppleMultitouchDriver.kext from your 10.6.8 install with the following steps....

Now how do you do this?

You may be able to manually drag-copy a backup of any previous version of this kext from your 10.6.7 /System/Library/Extensions to back it up somewhere...and then drag the new 10.6.8 one into that folder.... but I prefer an app called "KextHelper" (Google it) because it will make a backup of any original kexts it may ovewrite and puts them in your hard drive root....then it installs the one you want. Never send a human to do what the computer will do better 😉

Now, copying stuff, even with KextHelper, isn't enough.

You've got to fire up Terminal and fix some permissions on the files you've dragged over. Again, on your first pass, I would limit it to installing the first kext only, fix permissions, then reboot and see if it works before adding on the others.

So in Terminal, normally I have set the permissions for the whole Extensions folder including contained kexts but I don't want to screw up your rig... so while tedious, I'll just show you how to fix permissions on an individual kext and you would repeat for each one you've moved:

sudo chown -R root:wheel /System/Library/Extensions/AppleMultitouchDriver.kext

sudo chmod -R 755 /System/Library/Extensions/AppleMultitouchDriver.kext

rinse and repeat

When you are done fixing permissions on your files, run these commands:

sudo rm -rf /System/Library/Extensions.mkext

sudo rm -rf /System/Library/Caches/com.apple.kext.caches/Startup/Extensions.mkext

sudo diskutil repairpermissions /

[caution: sudo rm -rf is super powerful ... removes stuff... so just make sure you're pointing it at the exact right place!]

Now reboot and report back!

If your computer kernel panics, etc, try booting with the shift key held down to get into "safe mode" ... It will take awhile to boot in safe mode so don't panic (5-10 minutes?)

Alternatively, if you boot from a functioning install and connect/mount your hobbled drive...you can put the old drivers back in. You might not be able to use KextHelper because it may only act on your boot drive and not your target...but you can just move-copy the files you need around. But for the above terminal commands, you have to choose your target drive volume and not your boot drive! ... e.g. /Volumes/hobbleddrive/System/Library etc.

Then you can start over and try another variation/combination of kexts.

works! followed "The Procedure"....didn't have a firewire cable so used disk utility in the lion recovery HD to restore the image. after updates...no issues at all :)

A note about the last part of Step A. I had to Click OK twice after the nonsense about "Image Creation in Process. Cancel Image Creation to Proceed." The first time I clicked OK I didn't see the same message for about an hour. The second time was about 45 minutes later. After I clicked it a second time it took another five minutes to complete. ...I had the feeling it was not going to work.

@Roy, You're a trooper!

@Gravelle54, instead of setting up Verbose through Terminal on the Lion side, hold down option to boot into Snow Leopard but then let go and hold Command-V ,,,, this should get you into verbose mode on a one-time basis, for the Snow Leo boot attempt. See here: http://support.apple.com/kb/ht1492 As Roy says, you're going to see a lot of crazy stuff but you might see what lines it starts to "hang" on.

@jimtet, Doesn't sound like the Apple Techs you reached were able to run through "The Procedure".... it does work for iMac folks but the verdict for iMac'cers is that you'll get more performance if you request and utilize the factory install discs from Apple. If you call Apple back, they should send you the discs for 0-15$, depending on who you get. These special factory install discs for your iMac are probably all-white and have a version of 10.6.6 or 10.6.7 that was especially made for your iMac.... then you will be able to update from there as you please.

Don't destroy any backups you've got of your stuff before you do this because while you can downgrade your hardware, you might not be able to downgrade all your applications if you've already upgraded them... you may need a backup, an "archive and install", or some other migration technique to recover your stuff after you get a working Snow Leopard 10.6.8 on there. The Apple Techs might be able to help you with this part, for now you should order the factory restore discs for Snow Leopard 10.6.8 that used to come with your iMac.

After making five attempts at step "A" (the program crashed each time), I now have two words for anyone wanting to replace Lion with 10.6.8: Genius Bar.

They happily did a fresh install of 10.6.8 into my brand new iMac i5. No problems, no inqisition, no sweat. Took 'em seven minutes. By contrast, I spent a total of 14 hours trying to do it myself with disastrous results.

I have SL Server running on MBP 8,3 17" i7 Early 2011. No problems. Managed to use CarbonCopyCLoner to copy all my other stuff over to the new SLS install. Some permissions need to be fixed, but otherwise all looks OK so far - running Appleworks 6, Eudora 6.2 so far.

Played with Snow Leopard CLient in VirtualBox4.1.6 and it runs fine, but has issue with file sharing access (no guest additions support on mac) and virtual machien chewing CPU (known issue). Was going to try virtual SL on Lion as a solution, but happier to run SL for now.

According to iFixit readers, the target disk method works in 2011 Mac Mini. http://www.ifixit.com/Answers/View/58958/Snow+Leopard+on+Mac+Mini+2011

I used an external SL hard drive from MBP 1,1 to boot the MBP 8,3 and usd the Roy method on the fast new machine - took 40 mins to build.

@Harald Kohler ... Mac Pro should work. Just heed Roy's reminder/warning in the post above yours. Doesn't hurt to try it and if for some reason it doesn't work, you can come back to this thread for how to get your Mac Pro working. If you buy it from the Apple Store directly, you might be able to have the geniuses install Snow Leo for you!

@Ian Cheong ... I thought Targe Disk Method and The Procedure here (and derivations thereof) would work on the Mac Minis... I thought the main problem with the Minis (and iMacs) are that their Geekbench/Xbench scores are not the highest they can be. It would appear there is a driver/kext or something else missing from these "universal" builds we are doing that diminishes processor scores. However, because the results are still so fast, most people don't care. I believe it would take someone from the "alt mac" community to solve this problem but otherwise, I think these various methods will work for the Mini. At least that was my impression from feedback in this thread.

@JasonFear .... my early 2011 13" Macbook Pro shipped with Lion so it's entirely possible that Ian's Macbook Pro shipped with Lion. Since he refers to it as a "new SLS [Snow Leo Server] install," even if he were going from Snow Leo to Snow Leo Server, he probably had to use one of these methods to get it installed because it would not install from retail disc (unless he has the factory/restore discs for your model). He makes no mention of using the install discs to install his machine -- which, again, would not be possible unless they were the factory discs for your specific models. At any rate, there was no hardware change made to early 2011 machines that shipped with Lion vs. Snow Leo, the only difference between them is which OS they shipped with (with the SLeo machines shipping with restore discs, I assume, whereas the Lion machines did not).

With any newer hardware changes, heed Roy's reminder several posts above this one. Then YMMV.

Hi Roy,

I purchased a Macbook Pro 15" 2.0 2011 (October) which came with Lion 10.7. I tried to live with it but it was just like a circus performing tricks when I didn't need it. I stumbled across your post and followed your method to the T. I seemed to keep failing when trying to locate the system file in the image. Anyway I tried it a diiferent way, I installed my 10.6.3 onto VMFusion 4.1 updated to 10.6.8 (only build to allow Snow Leopard Client by accident:?) running inside lion. I then plugged in an external drive and connected it to VM, entered Disk Utility and restored snow leopard dirive to external. Once done, booted into Lion recovery and went to disk util like above and restored the new Lion drive to Snow Leopard. It all works great as I do audio production. The battery only lasts 3.5-4 hrs max on a brand new machibe very strange,

I will endeavour with your method of creating images though.

One last point, the exact words I was quoted by an apple tech at applecare. "Sorry sir I can confirm your machine will not run Snow Leopard 100%" You are wasting your time! - Why do you want to downgrade from am amazing OS likw Lion?? - This made me even more determined. I sit here smiling:))

I decided to let the folks at the apple store 'revert' my MBP back to SL for me. It was quick and painless. Took less than 15 minutes.

This may not work for everyone. I have an early 2011 MBP 15" i7 I bought from Amazon in Sept. It was supposed to ship with SL with the option for Lion, but instead came with Lion already installed.

Having the tech at the store do it basically meant wiping everthing and putting SL on there as if I had a new computer. If you are trying to keep your data, applications, or whatever this may not be the best solution for you. It worked perfect for me though cuz I didn't want the hassle.

This also was good for me since I didn't have that much stuff on it. I use this MBP pretty much only for school and film editing. I'm currently reinstalling Final Cut Pro 7, Adobe CS 4, and other apps. This is a bit of a hassle, but one that at least I know I can do (since I have all the discs).

Things are looking good with SL so far. Really good. Probably the biggest thing is, I can now actually connect to the University's WiFi, where previously I couldn't for some unsolvable reason (no one anywhere could figure it out).

So good to have a working laptop again. I feel great. Very much like the day I left windows.

Ziatron wrote:

You can go to the Apple "Genius" Bar and have them revert your computer to Snow Leopard for you.

On a recent trip to the Apple Store I encountered two customers that were having their computers switched from Lion to Snow Leopard.

That's good news because when I went in a week ago they said that I had to buy Snow Leopard separately and install it myself. I think they wanted me to give up, however and try again as it is the only thing preventing me from upgrading my laptop.

Great instructions Roy!

I can now dual boot Snow Leopard and Lion on my new MacBook Pro which came with Lion.

- Instead of restoring the 'external source prepared in B.7' to the original Lion Macintosh HD as you did, I had already partitioned the hard drive and so I restored 10.6.8 to this new partition. Leaving the original Lion drive and Recovery drive intact.

I then went on to transfer just my applications from my iMac running 10.6.8 during the Snow Leopard set up screens. Perfect.

Churrrrs

Ed

I did do parts a5-a9. I was just asking if it made a difference which computer the combo updater was downloaded on. I had already downloaded all the necessary apps and updater. However i'm doing it gain and making notes and taking screen grabs. Hope to post all that soon.

If you are going to downgrade lion you must do this first as a backup unless you decide to keep your recovery partition but for double backup safety i case your system has a HD failure:

Download Lion Recovery Assistant from Apple Support Downloads:

http://support.apple.com/kb/index?page=answerlink&url=http%3A%2F%2Fsupport.apple .com%2Fkb%2FDL1433&answerid=16777216&src=support_site.downloads.search

STEPS:

1. Plug in your lion system, boot, go through inital set up and get to the desktop

2. Download and install lion recovery assistant

3. Plug in a usb flash/thumb drive at least one gig i recommend 4-8

4. Dbl click th LRA and run it and follow instructions

5. Once it is complete you are done

6. Eject the thumb drive and keep it safe.

When you need to use it just plug it into a usb port restart the system holding down the option key and select Recovery HD. Once loaded you can do whatver you could do with the lion parition