Rigging Problem, Please help!

I have rigged a basic robot/alien model I made. When I go into pose mode and move the bones the model moves too but when I pull a bone up (The Blue Arrow) Nothing happens, It wont let me. Any help would be much appreciated, Thanks.

Any help would be much appreciated
Any blend files demonstrating your problem ?

I just found a solution, I couldn’t drag it, I had to use the G-Y to do it. My bad sorry.