Using a nSP and both OneNote App and OneNote 2016. Today I noticed that often the pen doesn't work in OneNote 2016. Its happened a half dozen times today. Nothing is greyed out, and I can select different pen widths, colors, etc.. I get the little visible queue on the screen when the pen tip is close, but no ink is left on the screen when I write. The only solution seems to be to close OneNote 2016 and reopen it, and then it works fine. I've not ever had this happen with OneNote App. It actually just happened again while I was typing this. About 15 minutes ago I was inking on a page. I started a Webex call and was typing this, and now I went back to take notes and no pen working. The nSP is docked and its had the OneNote 2016 application on the nSP display continually while I was working on the external display and external keyboard... so it just stopped working.