Server Connection Closed

Hi..I have been using Smart FTP for a while and have never had a problem...now all of a sudden I need to access MY OWN site via FTP and I can't...when I enter the ftp address/login/passowrd and hit connect it tells me the SERVER CLOSED CONNECTION....

I do not have this with any of the other sites I often FTP from...

does anyone have any idea why this is happeneing or what I can do?!?!?

Thank you so much!!!

Jill