The first thing you should do before installing Office 2016 is update Office 2013 to the latest version.

Remove the conflicting 2013 app

If you have a standalone 2013 app (such as Word 2013) installed on your computer, but a newer version of the app is already included in the Office 2016 suite you're trying to install then you'll get this error. For example, since Office 2016 includes Word 2016, the standalone version of Word 2013 can't coexist with the 2016 version of Word.

To resolve this, during the install of Office 2016, click Install Anyway. This installs the full version of Office 2016 and removes Word 2013.