Thanks for sharing your findings.

When the popup appears, there's a link about managing where to get software (or something to that effect). I chose that, and it displayed a list of options that included Windows NEVER telling me when I'm launching an app that came from somewhere besides the Windows Store (the option text was worded very poorly).

Not sure why the problem appeared after updating WinSCP, but choosing that option seems to have solved the problem.

I don't see a link to mark this question as answered, but I think we can put it to bed.

I just upgraded WinSCP from 6.3.1.0 to 6.3.4. I installed the .NET assembly to support my PowerShell scripting, and things seem to work fine.

But……every time I start WinSCP now, a dialog pops up telling me “The app you’re trying to install isn’t a Micros-verified app.” Even though I’m not installing WinSCP (already did that), just *launching* it.

I click the “Install anyway” button, then WinSCP launches normally.

This is incredibly annoying, and only started after the upgrade to 6.3.4. How do I stop this popup from opening every time?

I'm running Windows 10.