In the article How to Configure Windows Firewall for a Passive Mode FTP Server , it has been mentioned that stateful FTP filtering should be disabled so that the firewall does not block any FTP traffic with the command
netsh advfirewall set global StatefulFTP disable
Can somebody explain to me, why StatefulFTP should be disable?
As I understood that if the StatefulFTP is disabled, then the server firewall will not inspect the FTP connection to match inbound connection requests on port 20 with previous outbound PORT commands from the client. This will lead the FTP server to consider the inbound connection request for data from the client as unsolicited and block it.
