Microsoft has published a workaround for the Windows 10 Build 9879 Update Issue



From Supersite for Windows:

I promise you that someday I will stop writing about Windows 10 build 9879. But for now, at least, this prerelease version of Windows 10 continues to bedevil many of the users who are testing it, including me. So here's a new update in this long-running drama: Microsoft is now offering a workaround—not a fix, but a workaround—to help get the recent and crucial update installed.

And in my case, at least, it worked: The all-important fix for those ugly and persistent File Explorer crashes has been successfully installed.

The short version of the workaround can be found in Microsoft's support forums, and Microsoft's Gabe Aul recommended to me that I try it. Basically, it involves uninstalling four Windows Updates, rebooting, then installing whatever Windows Updates are subsequently offered, and then rebooting again.

  Microsoft Offers a Workaround for Windows 10 Build 9879 Update Issue