I have a FTP Server on a virtual machine, which is correctly redirected through the NAT.
But the windows firewall drops the packet, without logging it.
The logging is enabled, and the firewall logs into the file. But it doesn't log the port 21 requests.
When I create a rule for "Inbound Port - Any" and "Outbound Port - Any", the FTP works fine. So it is definitly the firewall, which blocks the traffic. When the connection is successful, the logs for port 21 are in the log file.
When I use "Inbound Port - 21" OR "Outbound Port - 21" and the other to "Any", the firewall drops the packet for unknown reasons and don't log into the log file. No line.
Wireshark analysis is showing, that the incoming packet on Port 21 is the only incoming (except of the TCP retransmission after that).
How should I configure the firewall correctly? Or configure the firewall at least so, that it says which Rule blocks?
Thanks in advance.