FTP Connection Hanging…

I am trying to connect to my company’s download site, which is through FTP via Java, and I get the connection box saying it’s trying to connect. It just hangs there. I rn the Network Diagnostic for WinXP and it says the FTP client is being blocked. I’ve checked my firewalls and nothing appears to be blocking it. I had access and then one day, just before Christmas, I couldn’t get in. Any suggestions? Am I missing something? How do I check my ports to be sure they’re open? Thanks for any help anyone can give!