The goal is to match your settings to the below screenshot, retrying and changing as needed until you find one that works for you 
For the TLS Support option the preferred order is Explicit, Implicit, and then No TLS (in order of encryption for the connection)
Some IT teams will block the encrypted transmissions, so you could check what setting you have, and bump down to Implicit or No TLS retrying each time until you find a setting that works for you
Typically Passive mode should be ticked as a standard

As always if you need further assistance with this or any other issues please reach out to the friendly PowerPro support team!