ftp cannot connect

I upgraded from the old version to the latest and now cannot connect to my server. I get this log error message:-
[16:41:02] SmartFTP v2.0.996.36
[16:41:02] Resolving host name ""
[16:41:02] Unable to resolve host name.
[16:41:02] Active Help: https://www.smartftp.com/support/kb/81
[16:41:02] Cannot login waiting to retry (30s)...

I have tried logging into my other server and that is the same. I have closed all firewalls etc and it still does not work.

I have used the remote service at http://www.web2ftp.com/ and that worked also for some reason dreamweaver does work.

My back up ftps also do not work ACT ftp and WS ftp.

All this has happened since I upgraded Smart FTP.

Have you any ideas.

[16:41:02] Resolving host name ""
Yes, the idea is to enter a host name, as it's empty ...