Hi Geoff,
thank you for your help. This is what is going on with the website as it is now:
http://www.justjason.nl/calendar/
And if I add the snippet to the functions.php I get a http error 500 notification that the website can not display the page.
This is the link to the theme I use: https://drive.google.com/file/d/0BxvG-eNee321bTFmSEJuTFNYazQ/view?usp=sharing
Maybe it is too late over here and I am too tired to see it, but I can’t see the option to make this reply private.
Thanks again,
Jason