Whichever web browser is set as your default browser is the one that will open when you click on a hyperlink in an email message in an email client (Windows Live Mail, Outlook, etc.). You can open a panel to set or change default programs by going to Control Panel and opening Default Programs.
Which web browser currently opens when you click on a hyperlink in an email message? That's a clue to your current default browser. And, you should have noticed that when you install a new browser, you are asked whether you want to make that browser your default browser. Usually, you can either accept or decline. And, you usually have an option to not show that message again. Thus, the need for a special panel, i.e. Default Programs in Control Panel, to set or change default programs.
Yet another way to change the default browser is within the settings for a particular browser.
