First start up in Safe Mode:
Start up your Mac in safe mode - Apple Support
Then remove all files in the red boxes. Yes, I agree with leroydouglas that all of those so called security apps should also be uninstalled. As you can see they did not help you at all. Anyways performing this step should resolve this initial problem for you and after deleting, restart again to exit safe mode and the pop up should not come back. If it does, then you will need to post those locations again.


I know the pics are a bit small, and can repost if needed.