MSIX App Attach with CIM

HOW TO: Use CIM for WVD App Attach

To use MSIX App Attach you need to extract an MSIX package to a VHD or a VHDx format to then mount the drive to the Virtual Machine. But there’s a third format that can be used, namely Composite Image Files System or .CIM in short. This is a new file system introduced by Microsoft to use in combination with MSIX App Attach. Why need a new file system? CIM provides better performance when compared to VHD(x). Microsoft preformed a comparison test between VHDX and CIM where they mounted 500 files in each format, each file being 300 MB. With the following results:

Average mount time356 ms255 ms
Average unmount time1615 ms36 ms
Memory consumptions6% (of 8 GB)2% (of 8 GB)
CPU (count spike)Maxed out multiple timesNo impact

As you can see the load on the machine with CIMFS is significantly lower than when compared to the mounting of VHD’s. This information was shared during the Windows Virtual Desktop masterclass. Microsoft host these sessions every few month and are free to follow, so make sure to sign up for the next one! The sessions are always packed with information and new announcements. That begin said let see how to create a CIM file.


Creating CIM file

The MSIXMGR tool has some handy functionalities backed in. Extracting a MSIX to a VHDx there were many steps involved like creating a VHDx file, mounting and extracting the MSIX and dismounting the disk again. The MSIXMGR tool automates these steps. Now we are going to generate the CIM files but the same steps can be used for the creation of VHD(x) files.

  • Open Command prompt in elevated mode
  • Navigate to the MSIXMGR location (c:\temp\msixmgr)
  • Run the following command
msixmgr.exe -Unpack -packagePath "C:\Users\Stephan\Desktop\ CitrixReceiver_3.0.1.0_x64__v1hrd262mcs5e.msix" -destination c:\temp\output\CitrixReceiver_3.0.1.0_x64.cim -applyacls -create -vhdSize 100 -filetype “CIM” -rootDirectory apps

In c:\temp\output you will find all the different .cim files. You will need all the files for in order to make this work.

If you don’t want to use CIM and just a VHDx file you can use the same command but simply replace cim with VHD(x).

msixmgr.exe -Unpack -packagePath "C:\Users\Stephan\Desktop\ CitrixReceiver_3.0.1.0_x64__v1hrd262mcs5e.msix" -destination c:\temp\output\CitrixReceiver_3.0.1.0_x64.vhdx -applyacls -create -vhdSize 100 -filetype “VHDX” -rootDirectory apps

MSIX App Attach

Copy all the .cim files you created to the file share that have been set up for MSIX App Attach.

In the Azure Portal go to your host pool and select MSIX Packages. Choose Add and provide the UNC path to the cim file. In my case this is \\man-0\appattach\CitrixReceiver_3.0.1.0_x64.cim. Make sure to put the State on Active.

640640Add MSIX App Attach Package

Go to your Application Group settings. Here you have two options. The first option is to include the application in the Default Desktop application group. The application will be available to the users when he signs in. Or you can create a remote application group which will only provide the remote app. In my case I will be using the default desktop group. So select the group, choose Applications and choose Add. From the dropdown you can select the newly added application. In my case this is Citrix Workspace. Make sure the assign the application group to you users.

To test sign in on the host pool where you should now see the newly added application based!

Other resources

MSIX App Attach on Windows Virtual Desktop

Windows Virtual Desktops App Attach has just gone into Public Preview. A new major step in delevering and optimizing Windows Virtual Desktop application management. This blog will cover to steps on how to set it up.

Wndows Virtual Desktop, Fslogix and App Attach

But first what is MSIX App Attach and why it’s going to help you with your WVD environment. When maintaining your environment there are generally three components that you manage. Namely the OS, User Profiles and Applications. On a laptop for example all these components are on a single device and the components stored on a single disk. This works fine for the laptop but if you have non-persistent environments you have a challenge. In an ideal situation you want to separate the user data, application data and OS data.


Separating the user information is something that has long been used and is especially handy when you work on non persistent environments. With Fslogix there is no need anymore for the User Profile Disk, which comes with all its limitations and performance issues. It works great for non persistent environments. This way the user data is seperated from the OS and the Application data and is stored seperatly.

MSIX App Attach

With MSIX App Attach you can separate the applications from the Operating System, the same way that you would use Fslogix to separate the user data from the OS. This way you will have three different entities that you can mange independently of each other. So if you would have to update an application you wouldn’t have to create a new golden image for example, but would only modify or create a new application package. This makes the deployment and updates management of your environment much easier.

Let`s get started

Here’s what I’ll be covering:

  • Create Share
  • Convert MSIX to VHDX
  • Configure MSIX App attach

There are a couple of thing you will need:

  1. A certificate to sign your MSIX package, this certificate also needs to be installed on the WVD session hosts. Check out my previous blog on how to to this; Deploy MSIX with Intune.
  2. Applications that are already packaged in the MSIX format. Also check out Deploy MSIX with Intune on how to set this up.
  3. For now your subscription needs to be white listed for MSIX app attach. Fill out the Microsoft form, with your subscription ID. Approval of request can take up to 24 hours.
  4. A Windows Virtual Desktop environment with session hosts which are based on Windows version 2004. Make sure that you set this host pool to an evaluation environment.

Create Network Share

To deploy the MISX packages to the Session hosts you will need a network share. This network share needs to be accessible for users AND to computers. So create two groups, one containing your users, one containing your WVD session hosts. All is needed are Read rights.

Prepare WVD hosts

First the automatic updates for MSIX app attach applications needs to be disabled. In a elevated command prompt run:

rem Disable Store auto update:

reg add HKLM\Software\Policies\Microsoft\WindowsStore /v AutoDownload /t REG_DWORD /d 0 /f
Schtasks /Change /Tn "\Microsoft\Windows\WindowsUpdate\Automatic app update" /Disable
Schtasks /Change /Tn "\Microsoft\Windows\WindowsUpdate\Scheduled Start" /Disable

rem Disable Content Delivery auto download apps that they want to promote to users:

reg add HKCU\Software\Microsoft\Windows\CurrentVersion\ContentDeliveryManager /v PreInstalledAppsEnabled /t REG_DWORD /d 0 /f

reg add HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\ContentDeliveryManager\Debug /v ContentDeliveryAllowedOverride /t REG_DWORD /d 0x2 /f

rem Disable Windows Update:

sc config wuauserv start=disabled

Furthermore Hyper-V needs to be enabled on the VM. To install Hyper-V run

Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V -All

Convert MSIX to VHDX

Before you can use the MSIX package, you will need to convert them to VHD(x) files (or .Cim but we won’t cover this today). Using the Microsoft docs, this is how you convert the MSIX.

  1. You will need the Hyper-V management tools. Install them by using
    Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V -All
  2. Download the msixmgr tool.
  3. Unzip the files
  4. Run the following Powershell commands to create a VHDx. Adjust the command s to your needs
New-VHD -SizeBytes 1000MB -Path c:\temp\chrome.vhdx -Dynamic -Confirm:$false
$vhdObject = Mount-VHD c:\temp\chrome.vhdx -Passthru
$disk = Initialize-Disk -Passthru -Number $vhdObject.Number
$partition = New-Partition -AssignDriveLetter -UseMaximumSize -DiskNumber $disk.Number
Format-Volume -FileSystem NTFS -Confirm:$false -DriveLetter $partition.DriveLetter -Force

5. Create a parent folder. In my case I will name it GoogleChrome
6. Run the msixmgr to expand the MSIX package.
.\msixmgr.exe -Unpack -packagePath “C:\Temp\Appattach\GoogleChrome_68.46.88.0_x64__v1hrd262mcs5e.msix” -destination “D:\GoogleChrome” -applyacls
The destination is the folder you created in step 4 and 5
7. Detach the VHDX and your are ready to place the VHDX to your packages location

WVD Portal

With the preparations in place we can now add the MSIX packages to our hosts pool. Because the feature is still in preview you will need to use the following link to access MIX package feature Go to your WVD app attach host pool, here you will see a new option, MSIX packages.

MSIX app attach

Select MSIX packages and Add to add a new package.
– Enter the UNC path to the VHDX file
– Enter a display name
– Set the state to Active

Add msix package
Add MSIX package

Now that the package is added you will need to assign the application to users. In you Host pool select Application groups. By default there should be at least one application group named after your host pool name followed by -DAG. To assign the application group to users go to assignment and add the users that need access to the host pool.

To add the MSIX package to the host pool go to Applications and select add:
– For MSIX Package select your added package
– Provide a Name
– Select Save

Add MSIX application

To check your work log in to the WVD host pool as a user and you should see the application that was added via MSIX app attach!

MSIX app attach final result

More info

Hopefully the information provided was helpful to you. You can also checkout the following sites for additional information:

Windows Virtual Desktop as trusted location for Conditional Access

When using Windows Virtual Desktop the public IP of which you are NATed to the internet changes consistently. In some cases you would want to have the traffic origination the WVD hosts to use the same public IP adress. So that it can be whitelisted to use some external service, or so that it can be used as a trusted location for Conditional Access. This way users can connect to Windows Virtual Desktop and be prompted for MFA, but once they are signed in, in a managed environment they aren’t prompted for MFA again.

Traditionally you could accomplish this setup by using an Azure Load Balancer. I didn’t find this very easy to implement, luckily Microsoft introduced a new service called Virtual NAT Gateway which make this a lot easier to implement. By using a Virtual NAT Gateway you can NAT your outbound connections through one, or more Public IP addresses. This way all the VM’s within a certain subnet of your virtual network will use a dedicated public IP to make outbound connections.

Please note that the Virtual NAT Gateway is still in preview, so I wouldn’t recommend using this in production environments.

To get started you will need a Virtual Network with some subnets, with a Virtual Machine deployed in that Virtual Network.

To create a NAT gateway, you select create resource and look for NAT Gateway.

Select your subscription, resource group and give the NAT Gateway a name and continue to the next step.

Here you can create or select a public IP address, if you need more one PIP you can also choose to create a whole range of PIPs. Notice that the SKU and assignment are Standard and Static, this means that the PIP you select won’t change over time.

Select a virtual network with the subnet(s) you want to associate the NAT Gateway, add tags and Create the NAT Gateway.

After the deployment is ready you can verify your settings by logging into the VM and checking your public IP on a website like

You could then add this IP as a trusted location to use with Conditional Access so users wont have to two-factor authenticate within a WVD session.

Deploy MSIX with Intune

I think we can all agree that application deployment is probably the most challenging part of an Intune implementation. The wide variety of Line of Business applications and different installation types can give you sleepless nights. It’s true that Microsoft has made some real improvements in application deployment with the support for most applications extensions. But there are always some applications that simply can’t be deployed with Intune or are very hard to deploy and manage.

With the introduction of MSIX I dare to say that you can now practically deploy any application successfully with Intune. In this blog I describe how you can create and deploy an MSIX package with Microsoft Intune.  In this blog I will cover:

  • Create a Self-Signed Certificate (testing purposes)
  • Deploy a certificate with Intune
  • Create a MSIX package
  • Deploy the MSIX package

Please note that in order to install MSIX packages you must enable Application Sideloading.

Create a self-signed certificate

Before you can deploy a MSIX package you need a certificate to sign your package. The signing of a package is a required step in the creation of the package. This is necessary because this is the only way you can assure that package is valid and came from a trusted provider. Preferably you should use a Code Signing certificate from a 3rd party provider. For now I use a self-signed certificate so that the deployment can be tested, but for you production environment I wouldn’t recommend this.

To create a self-signed certificate, you can start PowerShell as an administrator from any VM. Enter the following cmd, where you replace <Your Organisation> with a name of your choosing:

New-SelfSignedCertificate -CertStoreLocation Cert:\CurrentUser\My -Subject “CN=<Your Organisation>” -KeyAlgorithm RSA -KeyLength 2048 -Provider “Microsoft Enhanced RSA and AES Cryptographic Provider” -KeyExportPolicy Exportable -KeyUsage DigitalSignature -Type CodeSigningCert

To Export the certificate open certmgr, your certificate is located in the Personal Certificates folder. Select the certificate –> all Tasks –> Export. Choose Next –> Yes, Export the private Key –> Choose Next –> For Encryption choose AES265 and enter a Password –> Enter a save location –> and choose Finish. You now have the certificate with a pfx extension.

Export Certificate

We also need a certificate with the cer extension, so run the export Wizard again. Select the certificate –> all Tasks –> Export. Choose Next –> No, do not export the private key –> Choose Next –>   Enter a save location –> and choose Finish.

You now have the certificate to sign your MSIX package and you have a certificate to distribute it via Intune.

Deploy Certificate Using Intune

Before you can install the MSIX package on any machine the certificate to sign the application must be trusted by the machine. Otherwise the application wont start. To install the certificate on the machine we can use Intune to distribute the certificate.

From the Intune Management Portal go to –> Device Configuration –> Profiles and choose Create Profile. Here you enter the name and description of the Profile. For the platform you choose Windows 10 and later, for Profile type select Trusted certificate. In the new blade you select the .cer certificate that you exported. After you created the Profile you than assign the profile to a group with has a test device in it.


Create a MSIX Package

For this blog I wanted to package an application that I had some trouble with in the past, the Citrix Receiver.

I have copied the Citrix Receiver installation file and the pfx certificate to the packaging VM and have launched the MSIX Packaging Tool. Here I want to create a new package, so I select ‘Application Package’.


Select Create package on this computer and choose Next.  The packaging tool will now check some prerequisites and make sure that the drivers are installed.


In the next screen select the installation file. For now, I leave the installer arguments empty. For Signing preference, I select Sign with a certificate. This step is important. If you don’t select a certificate the application won’t be able to install.


Now provide some information for you package. Give your package a Name and a Display name. The Publisher name is provided from the certificate. The display name must be the same as the certificate, if these values don’t match the application won’t install. The installation location is not a mandatory field but is recommended.


By clicking next you will now enter the installation stage. The installation of your application will now start.  You can just run through the installation as you normally would. When the installation is completed you can continue by clicking Next.


If the application requires any first launch tasks, they can now be performed otherwise press Next and continue Yes, move on. The package will now be created.


Finally provide a save location for the package and choose Create.


Deploy MSIX with Intune

Now that the MSIX package is ready we can start deploying it with Intune. Simply go to the Intune management portal –> Client apps –> Add App. Here you select Line-of-business app. Here you can upload the MSIX package you created.


When you click the app information blade you can see that most of the information is already filled out with the information from the MSIX package. After adding the app, just wait till the application is uploaded. The final step is to assign the application to a group.

After some time check your test machine to confirm that the application is deployed.



As you can see the packaging and distribution of an application with MSIX and Intune is really easy. But it doesn’t stop here, after you deployed one version of the application you might want to provide the application with an update. With MSIX this process is even easier. So in my next blog I will show you can can upgrade the Citrix Receiver application to the new Citrix Workspace application!

Windows Virtual Desktop Management Tools

Windows Virtual Desktop is probably one of the most anticipated new products of Microsoft. If you haven’t heard from it, I would suggest that you start catching up ;). With the announcement of Scott Manchester GA (General Availability) just became a little bit closer.

There are plenty of blogs about how to set up a WVD tenant and sessions hosts, so I don’ want to go into detail on how to set it up. But if you have set up a WVD tenant you must have noted the lack of management tools. Or actually the absents of management tools, you can’t even find WVD in the Azure portal. Everything is managed with PowerShell, which can be a bit challenging. Microsoft did provide some management options for you but you will have to deploy them manually. They also require you to have an App service plan, which of course will cost you money, but you won’t have to use PowerShell for you management. Nevertheless I hope Microsoft will include these managements functionalities in the Azure Portal, but for now this is your best option.

WVD Management UX

The first management tool I would like to share is the WVD Management UX. The Managment UX helps you to preform basic management tasks. In here you can:

  • Create a New Host Pool
  • Add New Hosts to a Host Pool
  • Allow or block new connections to a host.(If you would like to drain the server for maintenance)
  • Create App groups. You can create App groups for Desktops or you can create App groups for RemoteApp
  • Assign permissions to App groups

Even though this may seem somewhat limited there are some extra functions you can use. However, these basic management tasks will help you a lot in doing day to day management for WVD.

WVD Management UX

If you want to use the WVD Management UX you can deploy it via the Github repository from Microsoft. The deployment will create an App service plan S1-Standard which will cost you around 70 euro/dollar each month.

WVD Diagnostics Tool

The second tool Microsoft has provided is the Diagnostics tool and it has just been released. With the introduction of WVD Microsoft also introduced some new RDS roles. We all know the Connections broker, Gateway, Session Hosts and we all know it was very hard to troubleshoot failing connections. Therefore Microsoft introduced the new Diagnotics role, which is also fully managed by Microsoft.

New Diagnostics role in WVD

Starting with the preview it was only possible to view the diagnostics using PowerShell, luckily Microsoft has made an App so you can troubleshoot using your browser. With the new Diagnostics app you can do the following:

  • Look up diagnostic activities (management, connection, or feed) for a single user over a period of one week.
  • Gather session host information for connection activities from your Log Analytics workspace.
  • Review virtual machine (VM) performance details for a particular host.
  • See which users are signed in to the session host.
  • Send message to active users on a specific session host.
  • Sign users out of a session host.

Unfortunately these functions aren’t available in the Management UX, you’ll have to deploy another application with an new app service plan. Which will cost you 70 euro/dollar extra each month, plus the additional storage for the log files. The deployment is pretty straightforward, Microsoft will guide you through the steps.

Example of diagnostics logging
Example of VM diagnostics
Here you can log off users and send them messages.