Perhaps the installer for version 1511 has repeatedly failed to run. There are many reasons why you might still be stuck on the original Win10. If you see 'Version 10.0 (Build 10240)' on the second line, you're still running the original July 29 RTM version of Windows 10. Start with the About Windows dialog (see screenshot), which you can get to by typing 'winver' in the Cortana search box and pressing Enter.

Here's how to check your PC to see if you're on the latest upgrade trail. Under normal circumstances I would attribute those kinds of problems to an unfortunate accident, but the poster insists that after he uninstalled the patch, everything worked properly. Poster H_He_Metals on Reddit complains that after installing the patch, 'Chrome crashed a few times, MS Edge crashed once, Desktop Window Manager caused the video driver to crash, My Murmur server even crashed, and the up arrow on the keyboard refused to work.' I've also seen several independent reports that the cumulative update knocked out Wi-Fi on various PCs, a problem that could only be fixed with a system restore. There's a complex five-step process to work around the error, posted by Microsoft as KB 910359, but it doesn't always work. I've seen complaints that people trying to install CU 4 are triggering an error 0x80070570, which is a general Windows Update error message. Of course, if your PC is still stuck on the July 29 RTM version of Windows 10 - build 10240 - you aren't getting any recent cumulative updates. This update includes improvements to enhance the functionality of Windows 10 Version 1511. The official Microsoft explanation for this new patch, known as KB 3116908, simply says: The sun may still be rising in the United States, but other parts of the world are already struggling with the latest cumulative update for Windows 10 version 1511 (aka build 10586, Threshold 2, or the Fall Update).

Win 10 pro version 1511 won't install