Error Cannot quit Microsoft Excel

Hi,
I am sharing here an issue in Microsoft Excel. I always receive an error message everytime I quit Microsoft Excel. See the attached screen shot below.
MICROSOFT EXCEL
Cannot quit Microsoft Excel
As I read on the error message, it’s very simple to look at, but very annoying because it pops up every time I quit Excel. My first remedy to this error was to remove Excel and install it again. However, it did not solve the issue.
I also did a virus of my computer for some viruses, but no virus was found. The only thing I did not do was reformat my computer. Please share some ideas on this issue. Thanks a lot.
