I have a problem regarding the use of digital signatures in a form. I have published the form to a sharepoint.
My problem is when I update the form and republish to the sharepoint. All digital signatures then become invalid and an error message is shown:
One or more digital signatures could not be verified. The signature field then shows "Invalid signature".
I have already checked this forum and a solution I found was to ste "Do Nothing" on the "form options - versioning". I have done some experiments with this using a very simple form on a test sharepoint location including one signature and one entry box and at first it seemed to look ok (although the updated text boxes are visible on the previous forms).
But as soon as I add a signature box to the form, when opening a form that is created with the previous version I get an error: "Infopath cannot open the file. The form contains schema validation errors". The details show the error "signatures2' is unexpected according to content model of parent element..."
I publish to the sharepoint as a "Document Library".
Can anyone help me with this problem? It is very important for us that the signatures stay valid after a small update of the form.
Thanks.
Martin