Currently Being ModeratedOct 25, 2012 8:44 PM (in response to selcor)
First, I recommend you update Lion with Software Update. Your OS X Lion 10.7.3 is two versions out of date, and updating it may fix whatever problem you have.
If you really want to downgrade and you do not have a Time Machine backup or "clone", then you must use the original System Install DVD that shipped with your MBP and erase the disk. Follow that with installing its original OS.
Find your System DVD, then read Kappy's procedure in this post: How do I uninstall Lion and go back to using Snow LeopardMacBooks iMacs iPods AirPorts, OS X Mountain Lion, 27 years Apple!
Currently Being ModeratedOct 26, 2012 2:27 AM (in response to John Galt)
When I start up my MacBook Pro without installation disk , it start with Mac OS X Utilities. I want to downgrade.
Currently Being ModeratedOct 26, 2012 3:18 AM (in response to selcor)
You can't downgrade without the original installer disc if it came with some version of 10.6. Even then, it entails either erasing, or installing on an external hard disk or flash drive. You can also install Snow Leopard server on Parallels if your Mac is newer than july 20, 2011. However, not everything that is Client compatible is necessarily server compatible. If you need access to 10.6 for Rosetta compatibility get an older Mac with the original installer discs. https://discussions.apple.com/docs/DOC-1948 explains how to downgrade if you already have an older Mac. Snow Leopard does not offer discless restore, unlike Lion and Mountain Lion.
Currently Being ModeratedOct 26, 2012 3:35 AM (in response to a brody)
I bought my MacBook Pro May 2012 with Mac OS X Lion 10.7.3 . Then I have some problem. Guest Log In appears and i can't log in administrator account, so that i decided to downgrade. But I try to downgrade and when it is start up and I insert my original installation disk, hold press c it said "You need to restart your computer. Hold down the Power button until it turns off, then press the Power button again." I restart it but it appear again.
Currently Being ModeratedOct 26, 2012 6:28 AM (in response to selcor)
Downgrading will not solve your problem. You have a kernel panic*:
Your machine is too new to use Snow Leopard without virtualization and Server mode.OS X Mountain Lion, * Links may give me compensation
Currently Being ModeratedOct 26, 2012 8:36 AM (in response to selcor)
I bought my MacBook Pro May 2012 with Mac OS X Lion 10.7.3
Then you cannot downgrade to any prior version of Mac OS X. Start the computer by holding ⌘ R, which boots OS X Recovery. When you see the OS X Utilities window appear, select the Utitlies menu > Disk Utility.
Repair the disk.
Quit Disk Utility.
Start your Mac and determine if your problem is fixed.
Currently Being ModeratedOct 26, 2012 9:24 AM (in response to selcor)
I bought my MacBook Pro May 2012 with Mac OS X Lion 10.7.3 .
This machine cannot be downgraded to 10.6, it's because 10.6 doesn't have the hardware drivers for your model of Mac.
This is why your getting kernel panics at boot time.
Your going to have to eject the 10.6 disk by holding the trackpad button and the option key down at the same time and boot the computer.
Usually the trackpad trick will work and the disk will spit out, but if it doesn't when you reach a row of icons on the screen keep pressing the eject key on your keyboard.
Once the disk is out, there should be a option to boot from OS X10.7 Lion, once you get in, set your System Preferences > Startup Disk to the Lion drive.
If you have trouble, reboot and do a PRAM reset.
Follow the list of fixes here to fix your machine.
Currently Being ModeratedOct 26, 2012 9:33 PM (in response to ds store)
What should I do? Upgrade it to Mac OS X Mountain Lion 10.8 ? It is the only solution?
Currently Being ModeratedOct 27, 2012 7:59 AM (in response to selcor)
Well the first question is whether you have a backup, because no upgrade nor staying still can be recommended until we know the status of your data. If you don't have a backup, use these instructions to restore your data first, so at least you have some semblance of a backup: https://discussions.apple.com/docs/DOC-1689 Once you are backed up, you can see if repairing the directory will help*: http://www.macmaps.com/directoryfaq.html
If that doesn't help, just restore your system to 10.7 using the directions from Apple after replacing your hard drive:OS X Mountain Lion, * Links may give me compensation