I’d like to place code in my Workbook_Open event that determines if there are any other Excel files opened in the current instance of Excel, and if so, closes them without saving leaving only the active workbook open. My end goal is to have only my file open in an instance of Excel by itself. I presume that I cannot develop code that opens up my workbook in a new instance of Excel from any other Excel file that may already be open. This would be ideal, but theoretically I cannot see how it can be accomplished as the workbook must already be opened before the Worbook_Open code can execute. Any help is much appreciated.