PKPsBit*1

How do you find out open ports in your Windows PC?

In the command prompt run the following command.
netstat -a -n

Example screen shot:
......................................................................
Active Connections

Proto Local Address Foreign Address State
TCP 0.0.0.0:23 0.0.0.0:0 LISTENING
TCP 0.0.0.0:80 0.0.0.0:0 LISTENING
.....................................................................
(Here telnet port and http port is opened,that means both services are running.If you want to close these ports either stop those services or use firewall)