If you are having issues with your Xbox One controller, please be advised that the windows 10 anniversary update seems to have introduced issues with the Xbox One controller drivers.
The following is from an arstechnica article.
On Tuesday, a Microsoft representative confirmed that the Xbox engineering team was working on issues with controllers' "exclusive" modes, controller connectivity with certain games, and Steam Big Picture mode seeing two controllers where there should be only one. No timeline was given for fixes on those issues.
Link to the Arstechnica Article
For now, please try this.
Right click the start logo and select the Device Manager
Scroll to the bottom of the Device Manager list and find the Xbox Peripherals (Expand it and Right-click on the Xbox Gaming Device)
Select the Update Driver Software… button
Select Browse my computer for driver software
Select Let me pick from a list .......
Select the old driver
and click Next
You may have to restart, or unplug and re-plug controller.