Test if external FTP server is running without logging in (SSH)

I am trying to use Azure to check our in-house ftp server to see if it is up and running.
I cannot log in because of security restrictions.
I am using visual studio and vb.net but can use other languages as well.

I don't want to create errors on the server either because eventually that would be considered an attack and would lock me out.

Does anyone know what the right approach for this might be?

stevieg wrote:

I don't want to create errors on the server either because eventually that would be considered an attack and would lock me out.

We cannot know what your particular server considers as an error. You can try to open (and immediately close) a plain socket connection to the FTP or SFTP (it's not clear from your question) port. But even that can possibly generate errors. In any case, this is not a WinSCP question.