Allowing app installs from “unknown sources” for Secondary Users on Android 4.4.2 I see that "Unknown Sources" under Settings → Security on Android 4.4.2 is greyed out (I can't enable it) for my Secondary user on my Nexus 7, Is it expected behavior? Is there any way to enable it?
Android by default does not allow secondary users (Restricted Profiles) to install apps from Unknown Sources.

But, under Application and Content restriction for the particular user, you can enable specific menu in Settings menu. You can check whether Unknown Sources can be enabled.