Running Windows as a standard user rather than with 'admin' rights removes over 90 percent of the risk" according to a recent study. (yes I know I have been going on about this for years):

Check to see if you are an administrator on your PC by right clicking on "My Computer" or "Computer" or "This PC" (depending on your Windows version) and chose manage.

This is especially important for home users or less computer savvy users.

Current versions of windows have made running as a non-admin for everyday access a lot easier. When you are installing software or a new printer most of the time you can just enter the administrator credentials when prompted to do so and it doesn't hugely get in the way of getting things done.

If you are running as just a lowly "user" on your own PC and you open an email or browse the web and see the administrator popup then you know there is something wrong because these things should require admin access.

At that point you can pause to consider if entering administrator credentials would be a good thing or not.