I don't remember whether previous versions of Windows had a "compatibility mode", but Win 10 does. I used to use the great instrument tuner "In-Tune" from Music Masterworks. IIRC it was used on my old XP machine. I don't recall it ever working on my Win 7 desktop. I recently started using my violin again and downloaded In-Tune to my now-upgraded Win 10 64 bit desktop. It wouldn't run. But if you right-click the desktop shortcut, it allows you to select "troubleshoot compatibility" mode. The system tries to run the application under various previous Windows environments. I discovered that In-Tune would still run under the XP compatibility mode, and that Win 10 would remember to use XP compatibility mode for the application in the future. This is a great thing to learn about. Musicians: In-Tune is now available for free here: http://www.musicmasterworks.com/creditorder.html I paid $15 for it back in 2004.