When you open multiple Excel 2013 workbooks in Windows 8, each workbook opens in a separate window but in the same copy or instance of Excel. However, there may be times when you want to open the second or third workbook in a new instance of Excel. For example, while you’re running calculations on a large workbook, and you want to work on a different workbook.
Here’s how you’d open another instance of Excel to view the second workbook:
Right-click the Excel icon from your taskbar.
While pressing Alt, click the workbook you want to open from the list.
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