Lg g5 won't let me install apps from unknown sources

[JJ Yoshi]

The app downloads but when i press to install...the install "button" won't work.

 

[B. Diddy]

Welcome to Android Central! First, the Unknown Sources option is turned on in Settings>Security, right?

If you have any app that has a Screen Overlay (like screen dimming apps), that can sometimes affect onscreen buttons. Try turning off the Screen Overlay (or uninstalling that app).

 

[korab84]

That's how it's meant to be with the Google Play Security feature.