The problem I had was that the language switcher plug-in was not showing the flags. The 
way to enable that the language switcher plug-in works, I have followed these steps:
1. Enable required plug-ins and modules.
(Extensions -> Plug-in Manager) -> enable : System – Language Filter
(Extensions -> Module manager) -> enable : Language Switcher (and publish it to become visible in front page)
2. For languages to appear in Language Switcher on front page, you must create dummy published menu for EVERY language you want to use.
This is example how to add dummy menu item for English language, so english language will be available as choice in Language Switcher. You should repeat it for every other language you want to add.
2.1 (Menus -> Menu manager -> add new menu) -> Title : menu-en
Menu type : menu-en
– Press Save & Close
2.2- Find your languagemenu in below table and click its name in “title” column.
– Click “New”
Menu Item Type : “Simple Article”
Select Article: I entered the article shown in the front page (in this case the article language has to be english).
Menu Title : menu-en
Status : Published
Default Page : Yes
Language : English
Press Save & Close
2.3 You will See Flag Appear near menu which meant this language will appear now as a choice in Language Switcher.
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thank you so much my friend
thanks to you for writing it, and google to help me find your page, i finished 3 days of headack 🙂
thank you
you’re welcome
For version 2.5 of joomla, the way to manage a multilingual site is quite different.
First the module language switcher is enabled by default at system level. You have to create a Module for showing the flags,
Key points:
1.- Enable:
– System – Language Code
– System – Language Filter
2.- Use Content languages to enable the places for
See it here:
http://www.ostraining.com/blog/joomla/joomla-multi-lingual/