I have a light switch at the end of the run. I would like to take power off that switch for an outlet that will always have power. In the switch box I have a black wire a white hot wire with black tape a ground and a red capped wire.

What does the switch control? The black tape on the white wire indicates that this is a switch leg. The wiring could have been set up to control a fan/light with two switches.

It controls 5 lights I wired it according to a diagram . I had to make the white switch a hot switch because there is no other wires feeding into the box.

OK, so the white is part of a switch leg to some lights. The black must be the other part of the switch leg. What does the red do? Why did you use 3-wire cable?

Can you show the diagram you used.