I have an excel workbook with a sheet of values formatted as a table. I use the Add a Custom Location Type in ArcGIS Maps for Office to join my excel data to an ArcGIS Online polygon layer. 40 of my joins fail because my polygon layer is currently missing some features (320 rows in my excel table vs 280 features in my polygon layer). When I attempt to save my excel workbook the document crashes and the map that I have added fails to save. Is it possible to save my map & workbook with errors? Why do the errors need to be resolved? I would like the excel sheet to be a work in progress with the ability to update the polygon layer with new features as they become available.