thanks for reply ...i did what you point to and still got the same error i looked for php mod_rewrite and it's working it put the whole site out of sub directory to the parent and still give me same error

If you haven't done it yet, call YOURSITE.URL/upgrade.php in the browser. This should flush the cache of Elgg where references to the old url might still be included. If this doesn't help, try deleting the system_cache and views_simplecache folders in the data directory to make sure that really no old cached files remain (these folders will get re-created automatically afterwards).

the problem solved by editing Apache server configuration in  httpd.conf by change AllowOverride None to AllowOverride All- then restart server and it's ok now ... appreciate your help