Hi Tom, This is Ramesh.
Windows doesn't have a built-in option to check for duplicate files. You may need a third-party solution like CCleaner or Auslogics to find duplicate files (based on file hash, not just the file names or size).
What is CCleaner’s Duplicate File Finder?:
https://support.ccleaner.com/s/article/what-is-...
Duplicate File Finder for Windows — Auslogics:
https://www.auslogics.com/en/software/duplicate...
How to Find and Delete Duplicate Files in Windows:
https://www.winhelponline.com/blog/how-to-find-...
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