Second HDD in optical bay not working properly
I have installed a second 1TB HDD in place of the superdrive but it is not working well.
File reads from that HDD, file transfers to and from that HDD all result in a beach ball. If I try to do big transfers the HDD vanishes from the system! I have to reboot to see the HDD again!
Searching online I found this - http://blog.macsales.com/14982-efi-updat...
I thought problem solved. The Apple site with the update also states its for mid 2012 macbook pros - https://support.apple.com/kb/DL1593?loca...
However whenever I try to install the update it states "This update is not for this system". I am not sure but I think this is because I have OSX El Capitan running, rather OSX Lion or Mountain Lion.
I have OSX ML on an external HDD. Should I use it to boot my laptop and then apply this update? Will putting back the drive with El Capitan after the update cause any issues?
Is there something else I can do or should I just get an Intel 320 600 GB SATA II SSD instead for the optibay?