By Fredrik Brattstig @virtualbrat
2025-December-17
Since last Friday (12 December 2025) – users using IGEL AVD might experience the “AADSTS50011: The redirect URI ‘https://mrs-prod.ame.gbl/mrs-RDInfraClient-prod’ specified in the request does not match the redirect URIs configured for the application ‘fa4345a4-a730-4230-84a8-7d9651b86739’. ” error when logging in to AVD, braking the login, and hinders accessing apps and desktops.
Here is a breakdown of the problem:
IGEL OS, has the possibility to connect to multiple workspaces (where a workspace in this case is seen as AVD ARM or AVD Classic).
AVD ARM is using a service principal client AppID “a85…“, while AVD Classic are using a service principal client AppID “fa4….“
As we can see in the above error message, the “fa4…” is failing to match the redirect URI.
Before we continue. AVD Classic (which is basically a renamed WVD (Windows Virtual Desktop) – Is supported until September 2026. This is important information.
Beginning Friday, 12 December 2025, some customers started experiencing login challenges, when their AVD clients was set to enumerate resources from AVD Classic.
In IGEL OS AVD App, AVD Classic resource enumeration is disabled by default – though, if you are a long ongoing customer/user, you might have inherited settings from past times, where AVD Classic enumeration is still disabled, based on that this was the default setting way back in time.
The solution/workaround.
The workaround, to avoid this error, you should disable enumeration of “Workspace-1” in the AVD configuration for your IGEL devices. This is done by disabling/unchecking:
System->Registry->app->avd->sessions->avdX->options->workspace-1->enabled->"Workspace Enabled" 
After applying this workaround, you will be able to complete the login, enumerate and launch resources from AVD ARM, though, no AVD Classic resources will be enumerated.
Why Microsoft changed the configuration in Entra for the Redirect URI for AVD Classic is still not communicated, to my knowledge. I have informed the correct persons at Microsoft, which confirmed a rollback of the configuration change made December 12 -25, Though, today, December 17 -25 another customer reported the same issues.
If you end up with having this challenge. You should log a support case with Microsoft for their visibility.
As Microsoft are going to stop supporting AVD Classic in September 2026, I recommend making sure that enumeration of AVD classic resources is set to disabled in your environment.
That’s it! Sorry for the disruption.
/Fred
VirtualBrat 