Welcome to Justanswer.com, my name is Dustin.I'm sorry to hear about the issue you are having, I will do my best to help you resolve it.
The correct way to do this, would be that after you set up your main admin account..
Then, set up a guest or non admin account.. That way if someone else is using the Guest or standard ( non admin account )
They would ALWAYS be asked for an admin password ***** install anything.
If you need help setting up that solution, let me know. If you dont feel that solution will fit your needs, please also let me know so we can discuss the issue further.
I strive to provide great service, and greatly appreciate a 5 star rating clicked and submitted when you are satisfied.. I always answer follow up questions.Dustin S.Senior Technician and Network Switching Systems Operator / Maintainer.
An add on for firefox or IE would only prevent firefox or IE from installing programs.. And it could be easily bypassed or stooped..
You could try pressing the windows key and S , typing in UAC and then turning the user account control settings to high.
Also, press windows S, type in smart screen, click change smart screen settings, click change smart screen settings again and make sure smart screen is on.
However, again the best way to do this ( and when used properly this is the best way to protect the computer )
Is to create a standard user account, and do most of your online activities from the standard account.. Its much much more difficult for viruses to invade your pc from a standard account because they wont have admin rights to run..
So as long as you keep your Admin account pristine, and use the standard account for most of your daily computer usage, thats truly the most effective setup..
Other then that, you can raise the user account control setting to max, and turn smat screenon.. Those two steps will g et close to what you want, without having to make a second, standard ( non admin account )
Dustin S.Senior Technician and Network Switching Systems Operator / Maintainer.
usually, for the UAC change to take effect, you have to restart the computer.
With that being said, As an admin user, you usually have full rights to install what you want.. (If you made a standard account, it would barely be able to open a program at this point without a password )
The only other option would be to either turn on parental control, or purchase parental control software.. But even then, it still requires that you create a non admin account. ( A standard user account)