Can't install apps

[gamin92]

Hi guys!

I've updated my v10 to MM. I have root, apps restored fine from the store and from titanium backup.
But strangely, I can't install any app "by hand", like installing updated app from Xposed, or an app downloaded like g4 tweaksbox.
When install screen pops, I can't click on "install", only "cancel works".
Any idea why? Any solution?

Thanks!

Edit : I sure ticked Unknown Sources

 

[gamin92]

OK I found, uninstalled Lux app and that works. Didn't have this problem on LP though.

 

[raging9]

I have LP and it happens to me. But sometimes it'll work if I keep pressing it. Its the Lux app creating the issue, tho?