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SkydiverFL
Mar 9, 2011, 09:22 AM
How can the Lion developer preview be removed from a MacBook Pro? The machine has a single partition with Lion. Unfortunately, now that Lion is installed, the laptop will not boot to a Snow Leopard DVD or a Disk Warrior DVD. And, of course, you cannot run the visual Snow Leopard installer from within Lion.

Any ideas?



qstyler
Mar 9, 2011, 12:24 PM
This might sound stupid, but anyway... Did you try holding C key while booting?
This should boot your mac from DVD

SkydiverFL
Mar 9, 2011, 12:27 PM
That's my point... it's not possible... C, D, X, option... DiskWarrior, Snow Leopard... no key command works. If I get it to START booting from the DVD it just hangs without ever loading the OS.

Basically, I'd like to simply blow the drive away. I'm pretty confident that it has something to do with 10.7 on the drive but 10.6 in the DVD drive. Hopefully getting 10.7 off the box will allow 10.6 to boot.

Sky Blue
Mar 9, 2011, 01:21 PM
Do you have another Mac and a firewire cable? You could try Target Disk Mode.

Eidorian
Mar 9, 2011, 01:23 PM
I hate to bring this up but you might want to reset the PRAM. It might be possible that Lion applied a firmware update but I find that unlikely. Anything that happens before OS X loads up is solely under the control of the firmware.

SkydiverFL
Mar 9, 2011, 01:27 PM
Nope, don't have another Mac, hard drive, or FireWire cable handy. Also, I've reset the PRAM... no dice.

Hellhammer
Mar 9, 2011, 01:30 PM
Lion automatically creates a recovery partition which has the same functions as the install disc so hold alt while booting and boot into the recovery mode. Then use Disk Utility to wipe the HD.

Sky Blue
Mar 9, 2011, 01:33 PM
just tried the following and it worked fine.

1. Booted into Lion on a test (;)) MBP.
2. Inserted retail 10.6 DVD.
3. Went to start up disk, changed to 10.6 DVD.
4. Rebooted into 10.6 setup.

Eidorian
Mar 9, 2011, 01:37 PM
just tried the following and it worked fine.

1. Booted into Lion on a test (;)) MBP.
2. Inserted retail 10.6 DVD.
3. Went to start up disk, changed to 10.6 DVD.
4. Rebooted into 10.6 setup.Oh yeah, the Startup Disk preference pane. I have not used that in ages but I have had the need to do so.

lighningblue
Mar 22, 2011, 10:28 AM
I am having the same issue, and when I try the steps above to boot from 10.6 Cd it stops at the apple Logo Screen and never goes any further.

izzyiz426
Mar 22, 2011, 01:42 PM
Im having the same problem. I have all of my data backed up, i just want to go back to sL. PLEASE HELP every time i put the dvd in it and press c it stays at the apple screen. and when i press option to load from the dvd it still doesn't work.

elrock
Mar 22, 2011, 05:19 PM
Lion automatically creates a recovery partition which has the same functions as the install disc so hold alt while booting and boot into the recovery mode. Then use Disk Utility to wipe the HD.

I used this method to restore SL from a backup, and it worked well.

jchambers
Mar 26, 2011, 12:19 AM
Burned a disc of developer preview
Restarted (+option) and then canceled the install of Lion
Opened up Disk Utility
Erased HD
Restarted from standaloneOSX 10.6 disk - this didn't work
Restarted from original factory installation disc (ie. the ones that come in the box with your computer) - this worked
Reinstalled 10.6

skottichan
Mar 26, 2011, 02:38 PM
Just out of curiosity, you all are aware that your computers will never boot from an OS CD that contains a version of the OS inferior to what was on the computer when it shipped, correct? Meaning the physical disc I have from the store that contains 10.6.3 (bought to upgrade my older iMac) will not upgrade any Mac that shipped with 10.6.4 or later on its restore discs, and exhibits the exact same "stuck at the grey screen with the apple" screen being described.

E00
Aug 27, 2011, 05:18 PM
Did all of the above and was able to get Lion out of the system and begin startup from OS X 10.6 with the original disc that came with my mcp. Problem: when I get to select the disk to install on, I get the "cannot start up from this disk" prompt. Partitions are fine, disc utility checks everything fine, Please help.

E00
Aug 27, 2011, 05:29 PM
Nevermind. Got it under control. I made an unjournaled image. After changing to OSX extended journaled, everything is installing fine. Thank you for the earlier posts.