Run a Macro On Open When Microsoft Excel opens a workbook, it looks at the code in a file called Auto_Open. There are some limitations to using this method. The Auto_Open Macro runs before any spreadsheets are opened or created, so you might see an error.   Before You Begin: Delete the XML Data Go to the Customer Table. Select Rows 4 through Row 771. Delete the data. Go to File->Close. Save your changes if you are asked.   3. Try This: Test the Auto_Open Go to File->Open. Find and select the Legs Eggs Pigs 2010.xlsx spreadsheet What Did You See? The data in the Customer Table has been refreshed. Exam 77-888: Microsoft Excel Expert 2010 4. Working with Macros and Forms 4.1. Create and manipulate macros: Run a Macro when a workbook is opened File ->Open