I am getting this error when I try to open a Scientific Notebook document in Duxbury. I have had no trouble in the past. The only thing different that I can think of is that I am using the sign for square root and the almost the same as sign in the document. I don't see how this could be the problem. The name of the document is square root, so that doesn't seem to be the problem either. All the other Scientific Notebook documents I have opened still open with no problem.Can anyone help?Susan _________________________________________________________________