Excel 2016 when opened opens only one instance. However, let us know if you are talking about the ability in Excel 2016 to open multiple spreadsheets in the same Excel 2016 window?
If yes, then this feature is not available in Excel 2016 and was discontinued since Excel 2013.
I suggest you to take a moment and send us your views and feedback about Excel 2016.
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products. Your feedback helps us know which features are most important to you. We appreciate your continued interest in Microsoft products and services.
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