I upgraded to Win10 and then found out iCloud will not work with it. Apple tech support wasn't aware until the troubleshooting suggested didn't work and he had to research it. My fear is the users for this is minimal and it may not get fixed at all. Using the browser iCloud is terrible. It's slow and will handle an alias, but I don't see how I can even add a second account of email I have.
PC to iDevices, Windows 10, iCloud app