Jquery validation plugin - TypeError: $(...).validate is not a function

You're not loading the validation plugin. You need:

<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.11.1/jquery.validate.min.js"></script>

Put this before the line that loads the additional methods.

Also, you should get the additional methods from the CDN as well, rather than jquery.bassistance.de.

Other errors:

[4.20]

should be

[4,20]

and

rangelenght:

should be:

rangelength:

For me problem solved by changing http://ajax... into https://ajax... (add an S to http)

https://ajax.aspnetcdn.com/ajax/jquery.validate/1.9/jquery.validate.js

Include jquery.validate.js before additional-methods.js.

$.validate() method is defined there

You didn't include the base jQuery Validation library:

<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.9/jquery.validate.js"></script>

Put that before the additional methods library. (BTW this is a hosted version, download your own if you want)