my Mac dual boots el cap and Windows 10. The Mac partition can use my iPhone's hotspot without a problem. The Windows partition used to be able to also, but since the last win10 auto update (the worst "feature" in win10) it cannot. Not a hardware issue, since the Mac partition connects just fine. I've done all the standard troubleshooting on both the iPhone and the Mac (Windows partition). I'm out of ideas. Any thoughts? Thanks!