Can't downgrade from El Capitan to Snow Leopard

E1326

macrumors newbie
Original poster
Mar 1, 2019
5
0
I want to install OS Snow Leopard on my iMac that currently runs OS el Capitan.


I've tried with an original DVD installer Snow Leopard from another iMac (mid 2007) and I can't start up from my disk. I've made a bootable USB key from my DVD and it didn't work either.


I originally wanted to transfer my data from my old iMac by Time Machine to El Capitan but it doesn't work so I've decided to try to downgrade, transfer my data and the upgrade to El Capitan.


My iMac Specs


OS El Capitan version 10.11.6

21.5 inch, Late 2009

Processor 3.06 GHx Intel Core 2 duo

Memory 12 GB


Can someone help me please


Thanks
 

CoastalOR

macrumors 68020
Jan 19, 2015
2,491
907
Oregon, USA
I want to install OS Snow Leopard on my iMac that currently runs OS el Capitan.

I've tried with an original DVD installer Snow Leopard from another iMac (mid 2007) and I can't start up from my disk. I've made a bootable USB key from my DVD and it didn't work either.

I originally wanted to transfer my data from my old iMac by Time Machine to El Capitan but it doesn't work so I've decided to try to downgrade, transfer my data and the upgrade to El Capitan.

My iMac Specs
OS El Capitan version 10.11.6
21.5 inch, Late 2009
Processor 3.06 GHx Intel Core 2 duo
Memory 12 GB

Can someone help me please
The installer DVD for a 2007 iMac would be Leopard (10.5) which is too old for your 21.5 inch, Late 2009 iMac. The minimum OS for your 2009 iMac is Snow Leopard 10.6.1.

You need to buy the retail Snow Leopard DVD:
https://www.apple.com/shop/product/MC573Z/A/mac-os-x-106-snow-leopard

EDIT: Or use the installer DVD that shipped with your 2009 iMac.
 

E1326

macrumors newbie
Original poster
Mar 1, 2019
5
0

E1326

macrumors newbie
Original poster
Mar 1, 2019
5
0
I'll check your link and get back to you if needed

Thank you
 

chrfr

macrumors G3
Jul 11, 2009
8,293
2,589
I'll check your link and get back to you if needed

Thank you
Snow Leopard isn't free software, so getting an installer from someone else constitutes piracy. You can get it here from Apple directly. https://www.apple.com/shop/product/MC573Z/A/mac-os-x-106-snow-leopard
If the installer disc you have is white, it's the same thing that Apple's selling. If it's gray, it won't run on your model Mac if it's intended for another Mac. Apple puts in a block for that.