I have one Mac running 10.7.5 and another running 10.6.8 that can be upgraded to 10.7.5. Unfortunately, I don't have an admin password for either, because the previous owner of the first died suddenly and the owner of the second -- that's me! -- can't remember the password. I'm trying to create a bootable external volume from an ESD dmg file but when I follow the procedures for doing it using the Disk Utility Restore option, it demands a password even though I'm not trying to modify anything on the computer.
Is there any way of getting around this using, perhaps, dd?
If I borrow access to another Mac, does it matter what OS version it's running if I want to use Restore? (I couldn't run the installer on a Mac running 10.11. It said something about operating system incompatability.)