I have solved the problem as follows. but it still same problem please tell me how to fix it.
thanks.
Language / Charset Problems - Things To Check
Some people encounter problems with garbled characters when using vBulletin with non-English languages. Here are some things you can check based on my experience troubleshooting these problems:
Make sure your HTML charset is appropriate to your forum language:
Admin CP -> Languages & Phrases -> Language Manager -> [Edit Settings] -> HTML Character Set
You might also need to set the MySQL charset in your includes/config.php file by uncommenting this line. This setting was added starting with 3.5.x:
// ****** MySQLI OPTIONS *****
// When using MySQL 4.1+, MySQLi should be used to connect to the database.
// If you need to set the default connection charset because your database
// is using a charset other than utf8, you can set the charset here.
// If you don't set the charset to be the same as your database, you
// may receive collation errors. Ignore this setting unless you
// are sure you need to use it. // $config['Mysqli']['charset'] = 'utf8';
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Also make sure your database collations are appropriate and consistent throughout the entire database. You need to use program like phpmyadmin to view your collations:
When you click your database name in phpmyadmin it will list all tables, their collations, as well as the collation of the database itself at the bottom. And when you click the name of a table on the left it will list the collations of individual fields within that table.
1) To edit the collation of the database itself you need to click the database name on the left and then click "Operations" on the top.
2) To edit the collation of an individual table you need to click its name on the left and then click "Operations" on the top.
3) To edit the collation of an individual field within a table you need to click the table name on the left and then click the edit image (a little pencil icon) for that field.
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If there was a database move involved then you might need to specify the character set when making the dump. This guide shows how: