Tried to open a port, but nmap says it is still closed
 

I've tried various things to open a port like
but nmap (nmap -sT -O my.ip.address) still says that the port is closed. It lists ports 80 and 22 as open, which they should be, so I have reason to believe that nmap is working correctly.

I'm trying to connect to this port and it is always refused. What can I do?

You also have to make sure something's listenning on that port.

Ah, ok, I've got it now, thanks