File_put_contents() is a PHP5 function. If you’re using PHP4 you will receive an error that the function is undefined. There are some “hacks” for PHP4 to add the function, you’ll have to search Google for them. Otherwise, you’ll need to upgrade to PHP5.
On a side note, the plugin isn’t detecting that I am running Apache. I am running Apache 2.x. I read somewhere that this plugin doesn’t like it if you install wordpress into the root of your site www directory. Any ideas?
Error Creating /var/www/.htpasswdaa1
FATAL ERROR! response code: 500
My thorough testing shows your server isnt good enough to to handle .htaccess / .htpasswd files. Switch to Apache