As usual I would expect it would take a couple weeks for Spartan to be compatible, as is usual for any updated browsers. Did Spartan (IE's replacement) automatically install with WIndows 10 today? Has anyone heard? Did it remove Internet Explorer? Are you advising your users of anything new about this?
I also here from our IT people that both Firefox and Chrome are about to do very significant upgrades also.
I'm thinking of sending an email reminding users to remember that it takes a few weeks for the world to adjust to a new browser, or an updated browser so it might be best to wait to adapt the newest version, and as always it is best to have several to try, in case one doesn't work.