I have read all the realted messages very carefully, and wasn't able to answer my problem.
I have customized the contact form, and I probably deleted a field that was in a realtionship from a tab because I accidently had it two times. (I did this for some fields.)
So I deleted it from one tab and left it in another. I do not even remeber which field it was
I am able to preview, but when I try to publich I get an error that doesn't tell me anything, and when I go to the create new contact I get the error that you see on the subject.
I do not know what to do on this. Probably if I achieve publishing everything will be fine
Any help is greatly appreciated