When you click on links from emails or documents, your default Web browser will open these URLs. For example, if you use Microsoft Windows, Internet Explorer is usually set as the default Web browser, unless you change it. If you install another Web browser, such as Firefox, you will most likely be prompted to change your default browser during installation. You can easily change your default Web browser at any time by opening the browser you would like to set as the default and adjusting the settings.
Firefox 3: Open Firefox; from the Tools menu, select Options. Click on the Advanced tab. Then make sure the General tab is selected. Click Check Now to see if Firefox is set as your default browser. If it is not set to default, you will be prompted to select Firefox.
Internet Explorer: Open Internet Explorer, under Tools, select Internet Options. Click on the Programs tab. Click on the Make Default button to set Internet Explorer as your default.
Safari: Open Safari; from the Safari menu, select Preferences. From the Main tab, choose your default browser from the drop-down menu.