Found the problem:
In my form i have a textfield that i use for the website url of the customer. If i use the full URL: http://www.domain.com i get the error but when i write the domain without http://
the error does not occur.
In my form i have a textfield that i use for the website url of the customer. If i use the full URL: http://www.domain.com i get the error but when i write the domain without http://
the error does not occur.