can anybody help me?  

Have you given the ftp program access through the firewall?
If the user name and password is right it should work.
I know on linux you have to specify protocols if you have a firewall and you would choose FTP and then choose a port to allow it to access from.
Does your router have a setup page? That might need you to allow your IP to use FTP and specify a port to do so.

okey dear rohit here what you do i m also a web hoster and a web developer and some time i also get these types fo problems so here is the deal
1)try to user cute ftp why? because it has resume support when you got dc it will resume ur file from you left
2) in user name put ur user name and in pasword put you password then in host if you have ur won domain name like www.rohit.com then put this in to you host name and simpley click okey and now click on ur site name on cute ftp and you are read to upload things if you got any more problem to tell me my email add on hotmail is [ webindus ]