Hi Dude, I am currently operating on a Excel file using an Excel UDF, every time I open the file with "$oExcel.WorkBooks.Open($filepath, Default, False) " and end with "_ExcelBookClose($oExcel, 1, 0)" to close the work file, while every time when there is a error happen before it goes to "ExcelBookClose", the Excel file will be remain openning and occupy a certain of resource, I used to have a long long process list of openning EXCEL.exe in my Task Manager, so I am calling for your help, if t