InfoPath 2007 crashes when signing a form. Error: Microsoft Office InfoPath has stopped working
I had to realize the other day that too many fields in the root of the form will make the form unsignable and the InfoPath application crashes.
To solve this problem create groups and split up the fields into (several ?) groups. I do not know where the limit is on how many fields can be in the root of the form. However, moving the fields out of the root made the form signable again.