Problem with Incoming FTP

New Comodo Firewall user here.

Firewall is mostly working well for me. One exception: I am using Filezilla Server as an inbound FTP server. The FTP server is on the trusted list of applications, and the local network is trusted.

When I attempt a connection from another PC on my local network, FileZilla Server see the inbound connection attempt, responds with an attempt to send the FTP welcome message, and then aborts the connection saying “could not send reply, disconnected”. I don’t see anything in the logs blocking the reply. Suggestions?

i wonder how something on your pc can get an “unrequested” incoming connection. have you set something that allows this?

normally a firewall would avoid in the first place that unrequested inbound connections get in. maybe you should check by this noticing if there is a “rule hole” for incoming things. (stealth port wizard, hide me from anyone).

sorry that i cant help with ftp, but i think this is a point that could be important though. if you used the stealth port wizard, you can make an exception for your ftp still.

You missed the point. The unrequested incoming connection (the ftp request) is passed to the ftp server correctly (not blocked). When the ftp server attempts to send an outgoing response (the ftp welcome message), the response is apparently blocked - the ftp server complains it can’t send the response.

ok, so you made the setting in the firewall for a server…
my worry was, that you can receive unrequested packets without setting an exception rule.

then it seems as if an outgoing rule is needed for your ftp program. you should make the server secure in a way that nothing can leak after “malicious” attempts. when the server reacts to ingoing requests, while having a rule which allows outgoing reactions to that.

make the rule as specific as possible.

Before I make the rule specific, I’d like to make the ftp server work!

there is a predefined rule for ftp programs.

have you used it for your ftp program? its chooseable in the question window if you scroll through “treat as”.

The predefined rule for FTP programs is for FTP clients. My problem is with an FTP server.

However, I’m happy to report that I was just able to solve this problem. The issue was some effect from a leftover piece of ZoneAlarm (which I previously used) which was not uninstalled.