Forum Discussion
Azure Virtual Desktop - Black Screens on logins - What we've tried so far
Unfortunately the KIR caused us more problems then it fixed. When we applied it we saw an improvement in the black screen at log in, but it broke 365 apps for half our users. The black screen was affecting roughly 5% of our user base and moving them to a new sever always seemed to fix it, so we rolled back to before applying the KIR because 5% of our users calling in is much better than 50%. We have also been working with Microsoft but not making any progress. It would be really nice if they would admit there is an issue rather than referring us to a KIR that does not work. We have multiple host pools that support both full desktop and app delivery. All of the host pools are equally affected but for the host pools that have App Delivery what the users see is a never ending connecting screen and they end up with a disconnected session on the host that we have to clear from the admin panel before they can log in.
GlenW1530 we have had this issue for weeks, started with black screens, fixed that with the KIR and then 80% of users getting Office 365 auth issues and no access to outlook etc. The only thing that helped us was going from 16 users per host to 8 per host with 1 cpu per user i.e 8 core machine for 8 users. Someone else mentioned it here and it seems over 10 users appx starts to fail and cause this issue. We also disproved anything to do with fslogix as this happens even when excluded from fslogix.
Also autostart all vm's before users come online to ensure they are "warmed up", spread the logins with "Breadth First", and look out for the AADbroker failing in event viewer as if this breaks, it breaks for all users on the host.
michealscott Same experience - applying the KIR decreases the black screen on logon but increases M365 auth failures, correlated with Microsoft.AAD.Brokerplugin crash.
- Hi,
I don't think the KIR is the cause, I think when the appx service crashes it will leave appx SID's of a particular user corrupted on the server, so when they next log on, it does not load it properly. The KIR will stop any further corruption happening but the damage is already done.
I have had to rebuild several session hosts from an old image to resolve this issue, apply the KIR and let Windows Update to October now and all is fine.
They did say run the following command on the affected session host:
Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}
That in theory should clear out any left over files or SID information for that particular user, whether it causes other issues, is your own risk to take.
This is what Microsoft have said about the particular issue we are facing:
“The Windows 10, 2024 7D Windows Update added the Undocked DEH feature added which has a bug in the profile delete path. A corner case of user logoff with Undocked DEH handler registered and profile delete via RemovePackage API in other user session causing appxsvc crash during another user logon. The targetUserSidString of logging off user isn’t updated.”
They are classing the Microsoft.AAD.Brokerplugin as a separate issue, whereas my argument is they are related and should be resolved with everything else.
Applying the KIR, start all VM in the morning and changing from Depth to Breath first has significantly reduced the black screen and O365 app issues.
Just a heads up, after going through the exact same issue within our AVD Environments we have narrowed the issue down to the Sept 14th Security Update. This patch has cause merry havoc with the AppReadiness Service and how it interacts with FSLogix. I had a 2 hour conversation with MS on Friday concerning this issue, where at first they stated there was no issues with their patch.
For now I have found the easiest solution was to rebuild my environments from a Golden Image Which did not include the September Patch, and manually update to August 2024 Patch then disable the Windows Update service.
After we had done this, we have once again seen stability within our AVD Environment, and have decided to implement a Dev Environment to test all future patches MS Decides to foist on us before rolling it out to general production.
Rebuilding the hosts from a W10 21H2 image from MS, uninstalling any update released after July 2024 and disabling Windows Update to prevent new updates to be installed is exactly what we did on our Windows 10 Multiuser AVD hosts to resolve the issue 100%. Implementing the KIR and changing the registry keys mentioned in https://techcommunity.microsoft.com/t5/azure-virtual-desktop/appreadiness-service-and-black-screen/m-p/1795520/highlight/true#M3241 did not resolve the issue, it only caused the issue to occur less often.
Everything works, including Outlook, OneDrive and Teams (new version) and no more black screens at sign in at all.
