iMac 27" mid 2010 now running Mountain Lion
wish to create dual boot Snow Leopard and Mountain Lion to run older scanner and other peripherals.
Original OS X install disc gives error message "you can't use this version you have 23.1.1
Created time machine backup.
Created bootable Mountain Lion USB
Created bootable Snow Leopard USB
Booted iMac from Mountain Lion USB and erased HD
Attempted to boot from original start up disc but it hangs on Apple logo screen
Attempted to boot from Snow Leopard USB and hangs at same point
Attempted to boot from Snow Leopard retail disc and hangs at same point.
Boots every time from ML USB
When I boot holding OPTION I can select from 3 different start up discs, but only ML gets past the Apple logo screen.
What is the reason why the iMac, which shipped from memory with
Snow Leopard, will now not start up from SL even when the HD has been erased?
wish to create dual boot Snow Leopard and Mountain Lion to run older scanner and other peripherals.
Original OS X install disc gives error message "you can't use this version you have 23.1.1
Created time machine backup.
Created bootable Mountain Lion USB
Created bootable Snow Leopard USB
Booted iMac from Mountain Lion USB and erased HD
Attempted to boot from original start up disc but it hangs on Apple logo screen
Attempted to boot from Snow Leopard USB and hangs at same point
Attempted to boot from Snow Leopard retail disc and hangs at same point.
Boots every time from ML USB
When I boot holding OPTION I can select from 3 different start up discs, but only ML gets past the Apple logo screen.
What is the reason why the iMac, which shipped from memory with
Snow Leopard, will now not start up from SL even when the HD has been erased?