I just upgraded my windows 10 pc to the 1511 version. I have (on the start menu) icons for photos, calendar, camera, maps, solitaire, news, get office, sports, one note all with a exclamation mark in a circle. When I click on any it says app not installed contact system administrator to repair or reinstall. I did a sfc/scannow and it came back with no integrity violations. As there is no iso available to reinstall I'm at a loss as to what to do. It takes nearly 50% longer to boot up compared to the previous windows 10 version as well. I tried searching for a former restore point to go back to but they all seem to have been removed after the upgrade. Icons on my task bar occasionally blink out then back on from time to time as well. Any advice will be appreciated. Thank you.