I installed a new window motor yesterday and now the motor is trying to work but window will not go down. Could something be bound up? Old motor was working but tripping the resistor. Was getting late and didn't have time to investigate.

 

You might not have meshed the motor gear properly to the regulator. You'll have to take a look.

 

That was the problem. I loosened the motor and re-installed and it is working fine.
thanks