Freeware to scan for open ports?

Is there any freeware tool, Win7 x64 compatile, able to scan my system for open ports? Portable and light would be nice

The point is to check, after any program install, if it opened any port...

Trying to figure how to close and stealth un-needed open ports in Windows 7, without a 3º part firewall...

Any sugestion is welcome!

(ps: sorry my english)

 

Try currports http://www.nirsoft.net/utils/cports.html .

 

Try ShieldsUp which can be found on Steve Gibson's site
http www grc com which is Gibson Research Corporation.
It will attempt to connect to your PC and it identifies which ports are open, closed or stealthed. It's fairly quick.

 

Seems like a winner

In addiction, i ´ve some few very noob questions...

- Can i turn a opened and needed port into a stealth one, or the program that need that port will not be able to access the internet?

- If i find a open port not that´s not needed anymore, should i first close it and then "stealth" it?

- How to easily open, close and stealth ports without the need of a 3º part firewall? Any small and cool program for that? Or should i "dig" into windows firewall advanced options...
Win7 x64 running here.
Thanks

Thanks for sugestion JW Clements, already tried it, its nice.

 

That isn't quite the way ports work.
From Wikipedia:
"The result of a scan on a port is usually generalized into one of three categories:
Open or Accepted: The host sent a reply indicating that a service is listening on the port.
Closed or Denied or Not Listening: The host sent a reply indicating that connections will be denied to the port.
Filtered, Dropped or Blocked: There was no reply from the host."
So Stealth indicates that there is something present. If there were no such host you should get a "destination unreachable" type response.

 

I use PortScan. It's multithreaded and portable. There is a review at http://www.addictivetips.com/window...r-common-ports-on-your-network-with-portscan/.