I’ve recently bought a 2TB My Passport and reformatted it to exFAT but cannot partition it anymore. I’m using it on a Macbook Pro that’s recently been updated to El Capitan. I want to partition it so I can use half of it for time machine to back up on it.
What happens when you try to partition the unit? Do you get an error message? What happens if you try a full erase before you partition the unit?