>I take it all you guys are comfortable with the expectation that VFP will run fine on Windows 10?

I haven't tested it myself but I understand it works at this time.

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As for "at this time" - in a nutshell, VFP9 will work on Windows 10 until it no longer does.

My understanding is Windows 10 is supposed to be the "last" version of Windows. It will be continually updated/upgraded without any major version number change. As such, these changes will from time to time be major, likely the equivalent of an R2 version (or R3, R4 etc.). As I explained in my first message above, at some point MS may do something that breaks VFP9. Will we have any advance warning? I consider it unlikely. VFP9 is outside extended support, MS has no obligation to support it in any fashion.

If we're lucky MS will checkpoint the OS - Windows 10 RTM, Win10 R2, Win10 R3 etc. That way users and devs running legacy apps can test at each major checkpoint to ensure compatibility. If VFP9 breaks at some point, at least we'll be able to say "Works with Win10 R3, broken with R4 or higher".

If they don't checkpoint, either someone has to test after each Patch Tuesday update (or maybe even more frequently if MS speeds up updates), or cross fingers and hope for the best.