I just upgraded to the latest "Cells" (4.4.3.1) from the old version (v3.8.1.0). Now the same sheet will not open and throws the following error: This Excel files contains BIFF7(Excel95 or earlier file format) record…...But will open in old version Aspose.Cells Product Family walt_schwarz...sample code and template file(s), zip the project and post it here...