Windows – Cumulative Update for Windows 10 for x64-based Systems (KB3081448) – Error 0x80073712

The reason for this is that for some reason the update has to copy files to one of those folders that is symlinked, and is unable to do so. It is looked at %systemdrive%\Users[whateverfolderhere] and is for some reason unable to move the file to where the Directory Junction is pointing.

In order to fix this problem, following these steps:

1. Open regedit (press Windows Key + R, and type "regedit)".
2. Browse to HKLM\Software\Microsoft\WindowsNT\CurrentVersion\ProfileList.
3. On the right, there are keys with "Data" values pointing to where different Profile folders are located. It should look something like this:
4. Change "%SystemDrive%" under "Default," "ProfilesDirectory," and "Public" to the correct drive letter (the drive letter for the HDD). In my case, this is drive D:
5. Restart your computer and try installing the updates again.

Just remember to change this if you ever change drive letters!

the workaround could not be simpler:

1. delete folder C:\Windows\System32\Tasks\Microsoft\XblGameSave
2. delete registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\CurrentVersion\Schedule\TaskCache\Tree\Microsoft\XblGameSave
3. Re-run the update

-> link to the solution