If you're experiencing an error message from Windows Update on Windows 10 Build 9926, that a new Build exists but it won't install, here's a fix.



From SuperSite for Windows:

After installing the latest build for Windows 10 (Build 9926), you might experience an issue where a new Build shows available, but when you attempt to download and install, it gives an error message (0x80246017) like the following.

Windows 10 Build 9926 introduced this bug and it will take a registry modification to fix it. According to Microsoft, Windows Update should've set the registry keys back to the proper value, but failed to do so. Microsoft will fix this issue in the next build.

  Fixing Error 0x80246017 in Windows 10 Build 9926