C:\WINDOWS\php.ini
;;;;;;;;;;;;;;;;;;;;;;;;;
; Paths and Directories ;
;;;;;;;;;;;;;;;;;;;;;;;;;
; Directory in which the loadable extensions (modules) reside.
[b]extension_dir = "C:\PATH\TO\INSTALL\DIR\OF\php\extensions"[/b]
....
;;;;;;;;;;;;;;;;;;;;;;
; Dynamic Extensions ;
;;;;;;;;;;;;;;;;;;;;;;
;
;Windows Extensions
;Note that MySQL and ODBC support is now built in, so no dll is needed for it.
;
...
[b]extension=php_gd2.dll[/b]
...
php_gd2.dll must be physically stored in "C:\PATH\TO\INSTALL\DIR\OF\php\extensions"