I have a seagate 500GB external hard drive that I have used on my old HP, I recently bought a brand new mac book pro, I have looked through a lot of forums to get an answer and have tried pretty much everything that people are saying. I have gone to my utilities and it shows up there but I can't do anything with it besides erase it. I don't want to erase it cause there is a lot of stuff I want off of it. I have gone to my preferences and checked all the boxes like everyone else said but nothing works. it still reads on PC's but it won't read on my MAC. I know the cable works cause it works on my seagate 1TB and it reads fine and I have tried rebooting my computer and there is no sercuity setting on the hard drive. Please some one help me, this is getting really frustrating.