Renor on "Contact form plugins don't work"

Hi all,

I really tried to fix this myself but I wasted too much time on this already.

My wordpress contact form plugin doesn't work. I started with CF7, coudn't figure it out, decided to try another one (Fast Secure Contact Form) and it's all the same.

Double-checked all the simple things. Turned off everything else (all other plugins). No go.

Pastebin from the "test" function here.

Thanks in advance.