I've tried many methods but still can't access it from external networks. Please help! Initially, the FTP service was directly established for anonymous logon. When I tried to log on via the intranet, I was required to enter the username "anonymous" and a blank password. When I tried to log on via extranet, it failed. I thought it was a security issue, so I switched to user logon, and configured a new user. When I typed "ftp localhost" on the host, I could log on successfully. When I tried to log on via extranet and clicked "This computer" for connection, a logon interface popped up, but errors 200 and 227 occurred when I entered the username and password. If I used a browser, I could log on after entering the account and password, but I only had access and couldn't upload or download anything.

The following three pictures show my configuration (vsftpd.conf) information: