Install PHP:

you will need the non-threadsafe version of PHP:

http://windows.php.net/download/

select the zip file. unzip it to c:\php

copy the file php.ini-dist to c:\windows

and rename it to php.ini

make the following changes:

max_execution_time = 600

error_reporting = E_WARNING & ~E_NOTICE

if you are using the latest version of PHP and the release date of vTiger is older you want to use the following

error_reporting = E_ALL & ~E_NOTICE & ~E_DEPRECATED

extension_dir = "c:\php\ext\"

cgi.force_redirect = 0

cgi.fix_pathinfo=1

fastcgi.impersonate = 1;

fastcgi.logging = 0

extension=php_gd2.dll

extension=php_imap.dll

 What you require is to ensure that IIS can execute the PHP scripts

http://in.php.net/manual/en/install.windows.iis7.php