In its continued commitment to interoperability, Microsoft has released a new SQL Server 2005 Driver for PHP. The SQL Server 2005 Driver for PHP Community Technology Preview (CTP) download is available to all SQL Server users at no additional charge. The SQL Server 2005 Driver for PHP is a PHP 5 extension that allows for the reading and writing of SQL Server data from within PHP scripts. The extension provides a procedural interface for accessing data in all editions of SQL Server 2005 and SQL Server 2000.
How to install driver
1. Download sqlsrv-for-php_version_language.exe to a temporary directory.
2. Run sqlsrv-for-php_version_language.exe.
3. Enter an installation directory when prompted. It is recommended that you extract the file to %ProgramFiles% with the default directory: “Microsoft SQL Server 2005 Driver for PHP”.
4. After extracting the files, read the Installation section of the Php_sqlsrv_readme.txt file for next steps.
Reference : Pinal Dave (http://blog.SQLAuthority.com)