I'm following tutorials on youtube by 3dsMaxHowTos for making bones and skinning a character.
My character has IK-solvers on the legs and the bones bend nicely.
When i add the skin modifier the mesh responds when i use the solvers for the legs, or when i rotate bones seperately.
Then i continued the tutorial (using my own mesh btw, not the preset zombie that goes with the tutorial) and started to adjust which vertex belongs to which bone for the left leg.
After i do this, the mesh no longer responds to any bone/solver movement.
I tried deleting the skin modifier and start over again, but it's the same problem now.

Any idea why?

(i'm new at rigging/skinning, so it most likely is a silly thing i did wrong)