I can't install Yosemite on an external drive

THC_SsSsSnake · 17 Nov 2015 at 13:56

I had no problem doing this in the past,i now run El capitan,don't know if that should make a difference but when I try to run the installer it says this copy of the install OS X is to old to be opened on this version of OS X.
what am i doing wrong please?

bloodiedathame · 17 Nov 2015 at 16:19

It's quite common, general Apple ****wittery, I think you might need to open the dmg with something like Pacifist. Google will be your friend for this issue.

Deleted member 77746 · 18 Nov 2015 at 12:15

Yeh because you have to 'boot' with some created media to downgrade. It's done by design.

THC_SsSsSnake · 21 Nov 2015 at 15:48

ok I created a n installer and got it to work,found info on one of the mac sites,