When you took the caliper off, did you take the brake cable off as well? Make 100% sure that it didnt freeze up. Next, take the caliper apart and clean all the insides on it and it should start working again. Stupid as the system may be, at least it usually easy to repair (it just needs fixing all the time!!)..
1985 Honda ATC 350X
2003 Yamaha Banshee
2003 Polaris Sportsman 500
There are 3 kinds of people in this world, Those who make things happen, those who watch things happen and those who wonder what the hell happend.