In your windows control panel you have a "game controllers" option. Bring it up. In there, you should see an entry for your joystick.
Click your joystick, and "properties" -- and look at the screen that comes up.
It should have a box with a little "+" sign in it that moves up/down and left/right as you move your stick. With your stick at rest you should see it near the center. As you push forward it should move up, and push left it'll go left.
Really basic setup 101 stuff. Make sure it's working okay. If it's NOT, go through the calibration setup. It will be in this same window (either on this or the next tab it has). Make sure you READ and FOLLOW each step as it comes up. When you are done go back and test the box with the "+" in it again.
Then once that's all done, and works in windows fine, go into aces high and in your clipboard settings calibrate your stick there. Make sure you calibrate ALL axis, including rudder, throttle, and X/Y (up/down/left/right).