Visual Studio 2010 setup project: How to set company name used in default install location?

Open the Properties Window (NOT the right-click on the set-up project)

Use the toolbar View -> Properties Window

VS 2013/2017 on windows 7:
Keyboard shortcut F4

VS 2010 on windows 7:
Keyboard shortcut sequence Ctrl + W and then Ctrl + P

Now select your set-up project in the Solution Explorer window, the Properties window should populate with the info (e.g. author, language, program title etc.) that you can edit