The Slingplayer plugin for Google Chrome was changed to an extension (as opposed to a plugin) when Chrome changed to a 64-bit browser from a 32-bit. Unfortunately, because of this change, setup.slingbox.com is no longer compatible in the Google Chrome browser (even though the Chrome extension that can be used to watch/use a Slingbox is still supported).
Windows 10 computers, however, do still come with Internet Explorer. You'll just need to search for it in your computer. Once there, install the Slingplayer plugin for Internet Explorer, and go to setup.slingbox.com. This should get setup.slingbox.com to work over Internet Explorer.
Here is the article on installing the Slingplayer for web plugin, just in case:
Hope this helps!