I'm using MS Excel 2010 on a Windows 8 laptop. When I double click on an Excel file, can't open my file. I receive this message: "There was a problem sending the command to the program."

The details:

Yesterday, I used imported data from a *.xlsx file. Yesterday, when I tried opening the files (in MS Excel) I needed for my Matlab project, I received a pop up box saying "There was a problem sending the command to the program." I thought I couldn’t open the same file in Matlab’s editor and using MS Excel at the same time

Today, I can't open any Excel files when I double click on them or when I right-click on the Excel icon (at the bottom of the screen in Windows 8) and click on my file. When I try to open my Excel files, I received a pop up box saying "The item you selected is unavailable. It might have been moved, renamed, or removed. Do you want to remove it from the list?" I clicked "Yes".

I tried double clicking on other Excel files and received this message: "There was a problem sending the command to the program."

I right-clicked on my desktop and created a new Excel file. When I double click on this file, I receive the same message "There was a problem sending the command to the program."

When I click on the Excel icon (at the bottom of the screen in Windows 8), I can open up Excel.

I restarted my computer today and still have the issue.

I can open my Excel files on another computer, though.

Thanks!