I am not sure what you mean in your explanation below by "Doing the correct things, taking the valve off halfway and "locking" the pump on" So lets try this:

1. Remove valve cap.

2. completely loosen the little nub at the top of the presta valve.

3. depress the valve, releasing a little bit of air (if there is air in the tube) to ensure the valve is not sticking.

4. Check to make sure your pump is not configured for shrader valves. If it is, change the configuration so it is for presta valves (if your pump is capable of pumping both presta and shrader valves this usually means the plastic piece inside the pump head should have the nub that depresses the sharader valve facing inward...you usually also have to flip the rubber gasket so the narrower opening is facing outward).

5. Attach your pump and lock it in place.

6. Pump up your tires.

If this does not work, reply to this post and try to describe more accurately what you are doing and what kind of pump you are using.

-j