Firefox can't establish a connection to the server at localhost in WAMP

I got this error while using wamp server
 

normally when wamp server is opened, with the link "localhost", or "127.0.0.1" we'll direct to this page,

 

There are several reasons to have this error.
1.If wamp server is not opened(:p)
2.Nomally Apache server use the port 80.But is some other process is using this port,this error may occur.(skype,system,IIS)
To get rid of this we have to end the other task which using port 80 or change the port which use wamp server.
End task of the process using port 80.
*Go to command prompt and type "netstat -ao"
 
*It will display currently used  ports of the PC and corresponding Process IDs(PIDs)
*Then notify the PID of port 80.here it's 4592.
*Then go to task manager and search for this PID and end the task.
*To set up Task Manager to show the PID column open Task Manager by using CTRL+SHIFT+ESC.
*Go to column / processes=>view =>select columns=>tick PID
*Then find the corresponding PID and end the task.

3.More consider if the PID of port 80 is 4.This means port is used by the system and we would not be able to end the task.(Normally this happend as I experienced by IIS,so we have to uninstall iis or should change the port of wamp server)

 There is another way of testing port 80,it's with wamp server,


 


2.changing the port of apache server
goto the "httpd.conf" file at the location  "C:\wamp\bin\apache\Apache2.2.21\conf"
 
change the port number as you wish(ex:8080===Listen xxxx)  then restart all services of wamp server and then try new link as "127.0.0.1:8080"




credits to http://techshamika.blogspot.in/2013/01/errorfirefox-cant-establish-connection.html