Because you didn't watch closely as you went through the install pages. There are boxes to uncheck. How? What browser?
Look in Add/Remove and see if Bing can be uninstalled. Depending on your OS, go to Internet options, the Programs tab, check to make sure IE is your browser.
When I downloaded Printkey from cnet, BING took over as my home page. When I go to Internet Options to replace it with my choice, the area is "grayed out".
Why did BING takeover my homepage?
How can I undo this?

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