I have installed:
PHP Warning: PHP Startup: Unable to load dynamic library c:\php\ext\php_sqlsrv_54_nts.dll - %1 is not a valid Win32 application.
in Unknown on line 0
There's a clue in the file name php_sqlsrv_54_nts.dll
The "54" refers to PHP 5.4. The SQL Driver doesn't (officially) exist yet for PHP 5.5.
Some people have worked on unofficial builds, but I would only use them for local testing. Microsoft sqlsrv extension for php 5.5.x
At present official releases only work with 5.4.x