Signature on document is invalid (inconsistent field signatures) when saving form

We have a relative complex form (a few sub forms, tabbed table, and web browser control object) that we can not save any more.If we remove the web browser control we can save, if we put it back on, we have the same problem.

This problem existed for some time, but usually the 5th time we try to save, it passed (huh?), and worked.

Now we can’t save the form any more, unless we remove the control. (copy of form or complete design or compact does not resolve problem)

I found same error messages for mail documents not design elements.

Anybody any idea?

j.