i was telling to GOD: help me, help me,help me plz ... then he gaved to me the way that i should follow, thanks to god and every one that helped here.
if you have a question mark ??

? ?? ? or the arabic files are installed but the content is in english read this
here you have how did virtuemart worked for me in arabic :
first of all make a backup plz (using akebaa backup).
problem1:
arabic files are installed but the content is in english or default language:
you should change the uppercase to lowercase here administrator/components/com_virtuemart/languages/, that s means change Arabic to arabic.
now it should work if not then you should have question marks ?? ??

? ? ,so continue reading...
problem2:
all my site show question marks

?? ?? ?? including joomfish translations ,that s means virtuemart and joomfish translations are showing ? ?? ?? ?? .
you should make sure that collation in mysql is utf8 general ci
if not then there is 2 methods
method1- before that you instal a new joomla site or a backup creat the mysql database that you will use and change his parametres to utf8 general ci ,then instal...
method2- if you already have the site working and it s big, use "phoca changing collation tools" it s free ,but it may break your site ,so doing a backup before is obligatory.
method3-this method is better than method2- make a backup with akebaa then reinstal the backup file and when you are in instalation windows of akebaa chose "force utf8" .and it s done.
problem3:
now the joomfish translations are working good but virtuemart translation are still in ? ?? ?? ??.
this was happening to me only online, in localhost it was working fine then when i uploaded the files to online the arabic was changed to


?.
i downloaded the arabic virtuemart files from here
http://joomlarab.net/extensions/new-components/372-Virtumart-1-6-6.htmlthen i didnt instal it i just copied the language files and past it in the mine (v1.1. 8 )
i changed Arabic to arabic following this nice forum.
then this is the solution for the problem3
the arabic files are saved in utf8, then i changed them into utf-8 without BOM , and that s was the solution. thanks to GOD.
to do that don t use the normal notepad,instead use notepad++ it s free and the best tool for working with html and css.whene you download it open the arabic.php file in notpad++ ,click encoding, click convert to utf-8 without bom ,then save.
that s all
i hope this can help non arabic too.