App-V 5.0 SP2 RDS Client with hotfix 2 breaks frequently on Windows 2012R2 with User Profile Disks enabled

Question

Hi All,
I am at my wit's end trying to troubleshoot this, so any help would be greatly appreciated.
We are having serious stability issues with App-V 5.0 SP2 RDS in our environment with User Profile Disks enabled.
We have applied the latest hotfix but the issues persist.
The main problems are:
1. Periodically the client seems to become corrupted and all applications stop working for all users. All applications including the official Microsoft Office 2013 ones - not just our packages.
The symptoms are the same as if I change the App-V Client Service account to run under a user account instead of SYSTEM, so it suggests a file access issue. The log files also hint at this, and one of there errors is similar to this:
The virtual application 'C:\Users\rds.user9\AppData\Local\Microsoft\AppV\Client\Integration\A3EF9C01-C0E9-4AC5-B21F-DB9B1D2F700C\Root\Mindjet\MindManager 14\MindManager.exe' could not be started because the
App-V Subsystem 'Virtual Filesystem' could not be initialized. {error: 0x6740090A-0x20003}
Once this problem occurs the only way I have found to fix it is to either completely remove and reinstall the client, or (perhaps this is the big clue) rename the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AppV\MAV\Configuration\Volumes , unpublish
an application, then republish said application.
I don't even think it matters which application gets published. The point seems to be that this 'Volumes' key gets rewritten.
I am highly suspicious that our issues are caused by User Profile disks in our RDS environment, as when I disable them on our staging collection all of these issues seem to disappear.
I have made sure all of the servers have permissions on the share (folder and share permissions). It doesn't seem to make a difference.
2.  Some application fail completely with User Profile Disks enabled. If we switch the setting from "Store all settings and data on the user profile disk" to "Store Only the following folders" there seems to be some improvement,
in that at least one application that fails on the other setting starts to work.
3. We have already set that NTFS 8 dot 3 reg fix some time ago.
SOS!
We have gone live this week (not my call) and this is having disasterous consequences. :(
Thanks in advance,
John

Answer 1

Hi,
Thanks for your response.
I did try this a while ago without success, although it may be worth revisiting with SP2 applied.
I have left this client now.
I left them a Powershell script that deletes HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AppV\MAV\Configuration\Volumes
and triggers an Unpublish/Publish of an application we have deployed to all of the servers.
This seems to work, but a fix would be better than a workaround.
Not really my problem now though - I did my best.
Thanks,
John