I have been struggling with many seemingly unconnected problems on my Surface Pro 3 i5 with Win 10 after the 1511 update. After many many frustrating hours, including online remote help from Microsoft, I narrowed the problem down to my user account being corrupted. My symptoms were that various apps e.g. weather, news, store did not work i.e they opened with a blank white screen or similar. The Action Centre stopped appearing when swiping from the right side of the screen. The start menu stopped working. Edge behaved randomly. Restarts took ages. It wouldn't shut down, requiring a forced restart (volume up plus power button). Updates wouldn't be detected or downloaded. Store stopped updating apps. The Surface crashed quite frequently. Wifi behaved "oddly" reporting it was connected when it wasn't and vice versa. Lots of DCOM related errors in Event Viewer. Lots of permissions related errors in Event Viewer. All very strange. I tried many things to solve this including a refresh from the latest windows 10 ISO (which worked for a while), deleting firmware updates etc etc. Hours and hours spent. I love my Surface but I was heading Apple's way until.... I set up a new user account, restarted and logged in with it, and hey presto, all the apps worked and everything seemed fine. I had previously been going down the route of corrupted firmware. Clearly that wouldn't be the case if everything works fine with another user account. So focus came immediately onto a corrupt user account being the problem. I gave that new account admin privileges, then deleted the main account I had been using (I have everything on Onedrive so this wasn't an issue, though it does save all your files anyway). I then logged in with the new account and used it to set up a new Microsoft-connected account with the same signin as the one which had been corrupted. Then after a restart, I signed in with that newest account, everything synced from Onedrive and all the apps & action centre now work. This is easier than doing a full windows reset as you don't lose all your apps and programs. I think the problem was triggered by the 1511 update somehow corrupting my main user account and it all went downhill after that. Hope this helps someone.