Cydia Sources not working properly NEED HELP?

okk so i added in a few sources wrong and it says failed and stuff, but then wen i add a source that is reall, it says "POSIX: connection refused" then wen i hit ok, after a few moments it says "sub-process/bin/bzip2 returned an error code (2)" after this, a list of this thing says "GPG error" and it has a bunch of stuff on it. can someone tell me how to fix this?