Problem:

If you are working with multiple Excel files along with documents (PDF, PPT, browser etc.), this shortcut key will circulate between all of the windows sequentially before helping you land on the relevant Excel window.

Solution:

Next time when you simply want to toggle between open Excel files, try Ctrl + Tab on an open window of Excel instead of Alt + Tab.
keyboard control ctrl tab

BTW  the same trick works with Browsers & PowerPoint (not Word). Try with different applications to see the effect.

Mogamboo views on ALT + TAB to toggle

 

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