Pre-installed MYSQL Server and WAMP MYSQL Server clash due to same port

I was having issue with installing WAMP server. Every things looks fine to me but WAMP server didn't turned to Green from yellow. Tried all the way available on google but didn't work.

Initially I thought it may be due to Apache server port, look for service using 80 port but there was none. Then I look more closely and it seems my Apache server is running fine it is my pre-installed MySQL server which was causing the conflict between WAMP MySql server

Stopped Mysql server-

Started MySQL server is still having Start/Resume Service as green-

While Started Apache server had Start/Resume Services as grey-

I opened the my.ini file and look for the port number and changed from default 3306 to 3305 or it can be any free avialable port.

[mysqld]

port=3306

changed to 

port=3305

It worked like charm for me. Hope someone also might get help from this blog.