HELP: cannot log in to server

When I try to connect to any server I am getting this:

[14:53:49] SmartFTP v3.0.1022.15
[14:53:50] Resolving host name "www.squash.ch"
[14:53:50] Connecting to 212.40.5.61 Port: 21
[14:53:51] Ein ungültiges Argument wurde angegeben.
[14:53:51] Client closed the connection.
[14:53:51] Connect failed. Waiting to retry (30s)...

I have used SmartFTP as demo version before and it always worked.
Now as I have decided to license it properly, it doesn't anymore...

Add SmartFTP to the exceptions in your software firewall and antivirus product.

Regards,
Mat

thanks, Mat, that helped