Hi. This appears when I open the workbook. It has something to do with sorting. The only recent change I made was using a side to side sort on rows. After this message I thought I could verify that something in the new sort was the issue. But, I opened/saved the workbook and then closed it without performing the sort and the error still appeared. I clicked the link and it gave me an xml doc that said the same thing. Anyone know what this refers to or suggestions for further troubleshooting.