Contact form problems

Hello,

I have a problem with my contact form, since i started to build my site the contact module was working. Last week i tried to install
a new module called ADV Contact, i was not able to get this module to work proper. But now i have a bigger problem.

In the header i put my secundary links one of them is "contact" when i click on it there is popping up a big white screen with failure message 404.

When i look in the menu on the contact ref. it should open the contact form. It looks that i mis this form somewhere.

Who can help me ???

Martien