I've read all the documentation, and tried every suggestion, but I'm still unable to run the mssql extension. When I uncomment the line in php.ini, PHP crashes. My system: Windows 2000 IIS 5.0 PHP Version 5.1.2-dev What I have tried: I've placed the ntwdblib.dll that came with php into the winnt/system32/ directory. Nothing. I've placed the ntwdblib.dll that is running on my mssql machine into winnt/system32/ directory on the php machine. Nothing. I've copied the php_mssql.dll into the winnt/system32/ directory on the php machine. Nothing. Any ideas would be greatly appreciated.