When updating your Windows 10 PC to the Anniversary Update, you may get this error: 0x80240031. If you can create an ISO for 14915 using the ESD file at C:$Windows.~BTSourcesInstall.esd (fyi, it is a hidden folder, created by Windows Update.), you could mount that and run setup.exe to upgrade. You might be better off waiting for the next build to be flighted to Insiders.

Windows 10 Error 0x80240031 Fixed!!!