Uncaught Error: Call to undefined function mysql_escape_string()

To help you out here... (too long for a comment)

Your require("config.php"); should contain the following:

Sidenote: Use the proper settings for your host.

$link = mysqli_connect("localhost", "username", "mpassword", "database") or die($link);

Then changing your escape functions to use the mysqli_ version of it and passing the connection parameter to it:

$name = mysqli_real_escape_string($link, $_POST['name']);
$lname = mysqli_real_escape_string($link, $_POST['lname']);
$uname = mysqli_real_escape_string($link, $_POST['uname']);
$email1 = mysqli_real_escape_string($link, $email1);
$email2 = mysqli_real_escape_string($link, $email2);
$pass1 = mysqli_real_escape_string($link, $pass1);
$pass2 = mysqli_real_escape_string($link, $pass2);

Again, same thing for the query. Using the i version and passing connection to it as the first parameter.

mysqli_query($link, "INSERT INTO ...

Check for errors on your query using mysqli_error($link);

So you could modify the query to read as

$query = mysqli_query($link, "INSERT INTO ...

and doing

if(!$query){
   echo "Error: " . mysqli_error($link);
   }

Also read the following on Stack in regards to API mixing:

  • Can I mix MySQL APIs in PHP?
  • You can't. mysql_ with mysqli_ or PDO etc. do NOT intermix together. You must use the same one from connecting to querying.

Footnotes.

Passwords

I also noticed that you may be storing passwords in plain text. This is not recommended. If you intend on going LIVE with this at some point, do NOT store passwords as plain text in your database.

Consult the following.

  • CRYPT_BLOWFISH
  • crypt()
  • bcrypt()
  • scrypt()
  • On OPENWALL
  • PBKDF2
  • PBKDF2 on PHP.net
  • PHP 5.5's password_hash() function.
  • Compatibility pack (if PHP < 5.5) https://github.com/ircmaxell/password_compat/

Other links:

  • PBKDF2 For PHP

Change your PHP version back to PHP 5.6 and it will working fine.