I can't get my toon to melee no matter what I do. I tried everything. No haymarker, nada. The only thing he will do is the rifle butt. What keys or buttons make him Kirk Out?
I hate the way bad buys come running into my shield generator. I need a way to stop that or drive them back.

What am I doing wrong?

If you have a weapon equipped, they will use the weapon.

If you want to melee, you have to remove the weapon.

If I remove it and hit numbers 1 and 2 for combos, the toon pulls the weapon out again and shoots.
I can't figure out what it is.

I assume you are holstering your weapon (H) instead, clear one of your weapon slots so you only have one weapon instead of two and then switch to the slot without a weapon (Z) you will then use melee attacks.

That must be it!
Thanks for the help...