Toolbox 3 is a web based software Tesla sells to allow you to reset error and change configurations on the car. A full instruction is way beyond my experience and beyond the scope of this tutorial. Here is a good thread on TMC about getting set up and configuring the laptop. Configuring that is one of the most challenging things. Pay special attention to the security settings in the browser. There are some people who are willing to log in remotely and help you and/or remote into your computer and connect with their account. TMC or one of the Facebook groups is a good place to look for them. If you just need one thing reset, this is a good option.