I have a home in Colorado that was built in 1959. It has 2 plug outlets and I replaced them with grounding 3 plug outlets. I was told that since the electical wiring was in conduit that I did not have to run an additional ground wire to each outlet. I've also been told that each outlet should be grounded by attaching a ground wire to the receptacle and the outlet box.

I've tested each outlet and none of them show an open ground.

Is it necessary to ground each outlet by attaching a ground wire to the outlet box?

Thanks for your input.