Merge pull request #298403 from dknappettmsft/avd-app-attach-cimfs-bug

AVD app attach add note for CimFS bug

Author: prmerger-automator[bot]

articles/virtual-desktop/app-attach-create-msix-image.md

@@ -42,6 +42,9 @@ Here are example commands to create a CIM disk image from an MSIX package. You'l
 
 You should create a new folder for the destination because a CIM disk image is made up of multiple files and this helps differentiate between the images.
 
+> [!CAUTION]
+> An issue currently impacts CimFS images with Windows 11, version 24H2, which prevents the images from being mounted. We are actively working on a fix that is estimated to be available in June 2025. Workarounds are use VHDX images instead or use a version of Windows 11 prior to 24H2.
+
 > [!IMPORTANT]
 > To guarantee compatibility, make sure the CIM files storing your MSIX images are generated on a version of Windows that is lower than or equal to the version of Windows where you are planning to run the MSIX packages. For example, CIM files generated on Windows 11 may not work on Windows 10.
 

articles/virtual-desktop/app-attach-overview.md

@@ -81,7 +81,7 @@ Before you can use MSIX application packages with Azure Virtual Desktop, you nee
 
 ### Disk image types
 
-For MSIX and Appx disk images, you can use *Composite Image File System (CimFS)*, *VHDX*, or *VHD*, but we don't recommend using VHD. Mounting and unmounting CimFS images is faster than VHD and VHDX files and also consumes less CPU and memory. We only recommend using CimFS for your application images if your session hosts are running Windows 11.
+For MSIX and Appx disk images, you can use *Composite Image File System (CimFS)*, *VHDX*, or *VHD*, but we don't recommend using VHD. Mounting and unmounting CimFS images is faster than VHD and VHDX images and also consumes less CPU and memory. We only recommend using CimFS for your application images if your session hosts are running Windows 11.
 
 A CimFS image is a combination of several files: one file has the `.cim` file extension and contains metadata, together with at least two other files, one starting with `objectid_` and the other starting with `region_` that contain the actual application data. The files accompanying the `.cim` file don't have a file extension. The following table is a list of example files you'd find for a CimFS image:
 
@@ -104,6 +104,9 @@ The following table is a performance comparison between VHDX and CimFS. These nu
 | Memory consumption | 6% (of 8 GB) | 2% (of 8 GB) |
 | CPU (count spike) | Maxed out multiple times | No effect |
 
+> [!CAUTION]
+> An issue currently impacts CimFS images with Windows 11, version 24H2, which prevents the images from being mounted. We are actively working on a fix that is estimated to be available in June 2025. Workarounds are use VHDX images instead or use a version of Windows 11 prior to 24H2.
+
 ## Application registration
 
 ::: zone pivot="app-attach"

articles/virtual-desktop/app-attach-setup.md

@@ -97,6 +97,10 @@ In order to use MSIX app attach in Azure Virtual Desktop, you need to meet the p
 > - All MSIX and Appx application packages include a certificate. You're responsible for making sure the certificates are trusted in your environment. Self-signed certificates are supported with the appropriate chain of trust.
 >
 > - You have to choose whether you want to use app attach or MSIX app attach with a host pool. You can't use both versions with the same package in the same host pool.
+
+> [!CAUTION]
+> An issue currently impacts CimFS images with Windows 11, version 24H2, which prevents the images from being mounted. We are actively working on a fix that is estimated to be available in June 2025. Workarounds are use VHDX images instead or use a version of Windows 11 prior to 24H2.
+
 ::: zone-end
 
 ::: zone pivot="msix-app-attach"