Installing PHP

First, extract the PHP package ( php-4.3.10-Win32.zip ). I extracted the package in the directory where Apache was installed ( C:\Program Files\Apache Group\Apache2 ). Change the new created directory name to php ( just to make it shorter ). Then copy the file php.ini-dist in PHP directory to you windows directory ( C:\Windows or C:\Winnt depends on where you installed Windows ) and rename the file to php.ini. This is the PHP configuration file and we'll take a look what's in it later on.

Next, move the php4ts.dll file from the newly created php directory into the sapi subdirectory. Quoting from php installation file you can also place php4ts.dll in other places such as :
In the directory where apache.exe is start from ( C:\Program Files\Apache Group\Apache2 \bin)
In your %SYSTEMROOT%\System32, %SYSTEMROOT%\system and %SYSTEMROOT% directory.
Note: %SYSTEMROOT%\System32 only applies to Windows NT/2000/XP)
In your whole %PATH%