Why Oh Why Oh Why.....does InfoPath produce this error and never tell you what field had this problem, I cannot fathom out what on earth the problem is......

 

argh!

 

Added 3rd Oct.....
Well, it went away after I deleted my form and assembly completely from the MOSS server including all the 100s of copies of my assembly which were stored not only under "Web server extensions" but also under "Temporary ASP .NET Files". I then rebooted the server and reinstalled my form and it all worked.
curious.....