With the command Netstat we can know what ports are listening and therefore we can troubleshoots some applications, with this command we are able to get protocol statistics (for UDP and TCP v4 and v6).
If you use the command netstat without parameters only display the active connections, but sometimes you need to know about a specific port, in this example you can use the parameters -a -n -o
C:\>netstat -ano | findstr 80
TCP 0.0.0.0:8000 0.0.0.0:0 LISTENING 4
TCP 0.0.0.0:38081 0.0.0.0:0 LISTENING 2436
TCP 0.0.0.0:49154 0.0.0.0:0 LISTENING 1080
and you will obtain what process ID is listening in the port 80 and which protocol as well.
this is a complete list of parameters to use with this command.
Displays protocol statistics and current TCP/IP network connections.
NETSTAT [-a] [-b] [-e] [-f] [-n] [-o] [-p proto] [-r] [-s] [-x] [-t] [interval]
-a Displays all connections and listening ports.
-b Displays the executable involved in creating each connection or
listening port. In some cases well-known executable host
multiple independent components, and in these cases the
sequence of components involved in creating the connection
or listening port is displayed. In this case the executable
name is in  at the bottom, on top is the component it called,
and so forth until TCP/IP was reached. Note that this option
can be time-consuming and will fail unless you have sufficient
-e Displays Ethernet statistics. This may be combined with the -s
-f Displays Fully Qualified Domain Names (FQDN) for foreign
-n Displays addresses and port numbers in numerical form.
-o Displays the owning process ID associated with each connection.
-p proto Shows connections for the protocol specified by proto; proto
may be any of: TCP, UDP, TCPv6, or UDPv6. If used with the -s
option to display per-protocol statistics, proto may be any of:
IP, IPv6, ICMP, ICMPv6, TCP, TCPv6, UDP, or UDPv6.
-r Displays the routing table.
-s Displays per-protocol statistics. By default, statistics are
shown for IP, IPv6, ICMP, ICMPv6, TCP, TCPv6, UDP, and UDPv6;
the -p option may be used to specify a subset of the default.
-t Displays the current connection offload state.
-x Displays the TCP connection template for all connections.
Cannot be combined with the other options.
interval Redisplays selected statistics, pausing interval seconds
between each display. Press CTRL+C to stop redisplaying
statistics. If omitted, netstat will print the current
configuration information once.