can't connect

One day I open SmartFTP and I can connect and upload files.
The next day, same settings, can't connect. Host is up (Yahoo). I saw that a SmartFTP update was available so I downloaded that. Still can't connect.

331-Enter your Yahoo! member password
[21:54:03] 331
[21:54:03] PASS (hidden)
[21:54:03] Connect failed. Waiting to retry (30s)...
[21:54:03] Server closed connection

frustrated as I just renewed with SmartFTP ...

Maybe its a problem on the server side? Check the username/password and contact yahoo web hosting for assistance.