Once you have good data to work with, it doesn't take long.........   Here's a fully functioning AutoIt to php encryption/decryption set for you to get started with!  (minimal credits to me - I only put it together - everyone else worked out the hard parts! AUTOIT CODE (change line 16 from http://example.com/your.php to your php location) #include <Crypt.au3> #include <IE.au3> Global $error Global $extended Local $str = "hello world!" ConsoleWrite("string to encrypt/decrypt