Here is one thing about Excel that drive me crazy - you can't have 2 files with the same name open at once. Why? Because of a "calculation ambiguity".
To be fair, I don't think I've ever had a problem with this unless I was being thrown Sheets/Docs via email which is a really bad thing to do to start with. Email is not a suitable document archival system!
Right tool for the job, or it's: http://wyorock.com/excelasadatabase.htm