I've been experiencing a particularly frustrating problem since upgrading from Windows 10 Pro v1511 Build 10586.494 to v1607 Build 14388 a few days ago (update: I am now on Build 14390 with the same issue; Build 14393 is downloading now but I suspect it will have the same issue as well). In fact, this is the second time I've installed a preview build since I had the same issue going from Build 10586 to 14385 and decided to restore my backup.
The issue is odd because Windows is otherwise working fine. I have no crashes or stability issues, games, programs and apps all run as expected and the Windows Store is finding updates for apps and games and installing them. The issue relates ONLY to the Windows Store and its apps and games, specifically with the installation of new ones. Windows Update is apparently working fine (although at the moment it is only finding and updating Windows Defender anti-virus definition updates). The problem is if I attempt to install any new Windows Store app or game, where the storage location is anywhere but C: (I have the default apps location under Settings > System > Storage set to H) then they fail after a small sub-1 MB download with error 0x80070005.
What I have determined is the following:
1. If I change the Storage location for apps back to C: (which is my Windows boot drive on an SSD by the way) then new apps and games will download fine, even those which previously repeatedly failed with error 0x800700005 when the location was set to H:.
2. With the H:\WindowsApps folder open while trying to install a new game or app from the Store, I can see folders being created and some files appearing in them. If the download fails with error 0x80070005 then the Store will try to download it again, at which point another folder appears. This repeats until I cancel the failed download and all the folders then disappear.
3. The Windows Store seems to be able to update apps and games which were already installed before the Windows upgrade regardless of whether they are on C: or H: (note: this may not actually be correct - see my second post below. However, apps and games installed on the C: drive DO appear to update and install fine).
4. I am unable to move any apps or games from C: drive to the H: drive or vice versa (correction: actually I can move games from H: to C:, just not C: to H: even if I have just moved them from H. Again, they fail with error 0x80070005 (which I believe is a permission issue meaning access denied).
5. There are three Accounts_Unknown entries showing under Properties > Security on the H:\WindowsApps folder. These accounts do not show on the hidden C:\Program Files\WindowsApps folder. These unknown accounts are (truncated as I am not sure the long string of numbers are relevant):
Things I've tried to fix the error are:
a. Taking ownership of the H:\WindowsApps folder (I use a standard admin account with the Microsoft account).
b. Setting all the accounts (Users, Administrators, etc) to Full Control and hitting Apply if they didn't have that access to start with.
c. Deleting the unknown accounts and hitting Apply.
d. Using Tweak.com Windows Repair All-in-One to reset the registry permissions and file permissions for both C: and H:.
None of those make any difference.
I suspect the issue is somehow linked to those unknown accounts but I am at a loss as to how to fix them. I have no problems with installing smaller Windows Store apps to my C: drive but larger games such as Quantum Break have to be installed to a different drive due to their size and the lack of space on my Windows SSD.
Can anyone point me in the right direction on how to fix this annoying issue please?