## Requirements

The SQLSRV extension can be used on the following operating systems:

- Windows Vista Service Pack 2 or later
- Windows Server 2008 Service Pack 2 or later
- Windows Server 2008 R2
- Windows 7

The SQLSRV extension requires that the Microsoft SQL Server 2012 Native Client be installed on the same computer that is running PHP. If the Microsoft SQL Server 2012 Native Client is not already installed, click the appropriate link below to download it:

- » Download the x86 package
- » Download the x64 package

The SQLSRV download comes 8 driver files, four of which are for PDO support. If you are running non-thread-safe PHP (PHP 5.3), use the php_sqlsrv_53_nts.dll file. (You should use a non-thread-safe version if you are using IIS as your web server). If you are running thread-safe PHP, use the php_sqlsrv_53_ts.dll file. Similarly for PHP 5.4, use the php_sqlsrv_54_nts.dll or php_sqlsrv_54_ts.dll depending on whether your PHP installation is non-thread-safe or thread-safe.

The most recent version of the driver is available for download here: » SQLSRV 4.0 download. If you need support for PHP 5.2 and/or PHP compiled with VC6, use the 2.0 release of the driver: » SQLSRV 2.0 download.

For more information about SQLSRV requirements, see » SQLSRV System Requirements.