Level 17 is really simple. Just open the source code and you will find how to get the password for this level. You will see something like this in the source code; Password: your IP address, yes this is it.
IP stands for internet protocol address. Every connection has one of its own. You can check your by googling or visiting any of these given sites.
Just copy and paste your ip address and press login. Next page comes up with an error.
Warning: Cannot modify header information - headers already sent by (output started at /home3/jskenned/public_html/hackertest/unavailable/Ducky.php:12) in /home3/jskenned/public_html/hackertest/unavailable/Ducky.php on line 58 ../level18.shtml
But, here you get the link to level 18. Good luck!!!