FTP service 2 1 port, Telnet service 23 port and SMTP service 25 port are closed: Start-Run -CMD.net stops Telnet; 135, 139 and 445 are the back doors of virus trojans. The port closing solutions are: Control Panel-Administrative Tools-Services-Find Remote Procedure Call (rpc), Right Click-Properties-Service Status-Disabled, OK 139 ... Right Point-Network Neighborhood-At the top of the column that appears, the IP Settings /DNS/WINS/ option appears, and then click WINS, with NETBIOS settings at the bottom. Change the default value to disable NETBIOS over TCP/IP and confirm. Care 139. Solution for closing port 445: Right-click-Network Neighborhood-Properties/Local Connection-Properties. Remove the box in front of Microsoft network client and 445 will be closed. 3389 is a vulnerability of remote control port 3389, that is, XP will automatically create a new account and an account with an empty password.