Firewall Ports for POP3 Secure Socket

I’ve got a web app that checks a mail server for incoming mail, processes it, and sends out replies. Don’t worry - it’s basically an internal system and does a lot of validity checks before sending out the reply.

Run locally in the debugger it works just great. For the POP connection it starts on one port (say 993), and i guess after the secure connection has been negotiated the port switches to something like 50212.

Running on Xojo Cloud I am having issues with the firewall ports. I start by opening the initial port for outgoing traffic (and FirewallPort.IsOpen always returns False, so I am ignoring that check for now). I guess the negotiated port # is returned on 993? Do I need to open 993 for incoming traffic to get the response? And then open a new firewall port with the negotiated port?

I haven’t been down this road before, so i would appreciate some advice…


Hi Cliff - That sounds correct to me. I haven’t tested that exact setup but it sounds like it will work.

Thanks @Jason_Parsley, I’ll give that a shot and see how it goes.

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@Jason_Parsley, I tried opening the initial port for incoming traffic and I get this error:

Incoming firewall port must be greater than 1023

Well… it’s working now without opening any incoming ports or re-assigning port numbers.

I have been adding a lot of logging and exception trapping and a couple things came up, so i guess in the process of fixing those the real issue was solved.


@Clifford_Antrim Ok, thanks for the update. It’s great to hear that it’s working now!