Issue reinstalling Snow Leopard

[ccbc]

Just found a well-maintained MacBook Pro late-2006 (specs) for dirt cheap. Beside the swollen battery and an irresponsive trackpad (probably related to the battery), it was running fine with Mac OS Lion, but I wanted to downgrade to Snow Leopard. To achieve that, I copied the Retail DVD from archives.org on an external HDD.

Install went fine, reboot to a login screen. I had no user/pass... Decided to reboot. It now shows the prohibited sign and it doesn't boot to the login screen. I reinstalled Snow Leopard a second time, same result.

Cmd+S doesn't solve anything, Cmd+R doesn't seems to work.

Any idea folks? Thanks in advance!

Also, why can't we use a USB key to copy the iso on it and boot from it? The technique works with an HDD, but not with a USB key.

 

[theMarble]

I would try re-installing Snow Leopard but first erasing the hard drive in Disk Utility, if that doesn't work the hard drive might be failing.

Also, why can't we use a USB key to copy the iso on it and boot from it? The technique works with an HDD, but not with a USB key.

You can't simply copy the ISO over, you need to use the "Restore" function in Disk Utility. Then it will be bootable.

 

[Amethyst1]

If it still doesn’t work after that, the ISO may be corrupted. I’d try another one.

 

[ccbc]

If it still doesn’t work after that, the ISO may be corrupted. I’d try another one.

I installed the iso you suggested. Now I can boot without the prohibited sign, but I end up at the login screen. Progress I guess. I still don’t get why it asks for user/pass when the install didn’t prompt to create one :-/

I would try re-installing Snow Leopard but first erasing the hard drive in Disk Utility, if that doesn't work the hard drive might be failing.


You can't simply copy the ISO over, you need to use the "Restore" function in Disk Utility. Then it will be bootable.

I did use balanaetcher to copy it successfully on a USB stick. Unsure why it didn’t work with Disk Utility.

 

[ccbc]

Ok, fixed the issue. I found the Reset Password function on the install disc. But for whatever reason, thr 10.6 reinstall didn’t format the drive, kept the data from previous users and only downgraded from 10.7 to 10.6. That explains why it asked for a password after the reinstall.

 

[Amethyst1]

Cool. Since downgrading isn’t officially “supported” (AFAIK) and might cause issues, I’d probably consider wiping the drive (Utilities > Disk Utility after booting from the 10.6.3 install drive > Erase tab) and reinstalling a fresh copy of Snow Leopard, assuming there's nothing on the drive you want to preserve.

 

[ccbc]

Hdd erased and reinstalled properly. Thanks!