how do I upgrade from OS 10.10.5 to 10.11 on MacBook Pro mid 2009
I'm running a MacBook Pro 15", 2.53 GHz processor built in mid 2009. It has 4GB of 1067MHz memory. It is presently running OS 10.10.5. I need to upgrade to 10.11. All of my attempts have resulted in the message that 'you can't install that version on this computer. Is there a path for me to make the necessary upgrade?
PowerMac, Mac OS X (10.2.x)