I've just got a second hand mac mini server (mid 2012) and despite being 'wiped' it still has an admin password and a lot of the old user's software still installed, as well as a lot of tedious settings etc. I restarted it with cmd-r held down, and got no further than the boot screen before it restarting again and telling me the familiar kernel panic message 'Your computer restarted because of a problem'. I can boot into startup manager, where I can see the recovery drive, but selecting it again results in a kernel panic. I cannot boot into safe mode. Does anybody have an idea of what might be causing this? It's really annoying me as I just want to use my new mac! Thanks.