Hi New to these forums but have 'hovered' around them for ages... Thought I'd better sign up My 2012 Mac Mini running Yosemite still has niggles when it comes to my external 3TB HDD (Seagate) I use it as my TimeMachine and for general storage (MS Word & Excel files, email back-ups and iTunes stuff etc...). However the main iTunes account is on the Mini's own HDD The external HDD every so often is booted even though the Mac Mini is asleep; I've already googled this many times and done the suggestions (turned off power saving et al) I rarely shut my Mini down, just put it to sleep but I have bought & use Jettison which seems to work 90% of the time but still... The external HDD gets booted and when I switch on the Mini from sleep, it's not there and I have to unplug it/plug it back in to get it running again (not ideal I know) Any further suggestions?!