99 contour speaker install problem

Hi, I installed new speakers, however they stop working. I took the door apart to check, and the wires were pulled out of the speaker. I think the window may have knocked them off. How do I prevent this from happing again.

Roll the windows all the way down before installing them and make sure the connections are tight.

Thanks for the help, I never installed car speakers before. I didn't have any problems installing them, I didn't know the windows had to be down in order for everything to go smoothly. I bought the ford speaker harness from a website. When I installed the speakers, I didn't have to cut any wires. I just connected/pluged everyting up.

Either way, he's right. with the door panel off roll the window all the way down and see if it hits the harness.