App Layering

What’s new

Citrix delivers new features and improvements to Citrix App Layering users when they are available. New releases provide more value, so there’s no reason to delay updates.

This article covers new and enhanced features and improvements in the current release, and all other App Layering versions released in the last two years. The Upgrade path and Labs feature in the current release apply to all App Layering releases covered in this article.

For the latest App Layering requirements and supported platforms, see System Requirements.

App Layering 2107 (This release)

August 2021

This release supports the following Windows versions, hypervisors, and connection brokers.

  • Windows 10 version 21H1
  • Citrix Virtual Apps and Desktops 2106
  • Citrix Provisioning 2106
  • VMware Horizon View (JIT only) 8.2


  • After upgrading from vSphere 6.7 to vSphere 7.0 Update 2 or later, you can now create layers and publish images with VSAN storage. (ALHELP-1410)

  • After upgrading to Windows 10 1909 or 20H2, ClickOnce apps now work with existing user layer disks. (ALHELP-1425)

  • An app layer that is assigned to a subset of users on a machine and contains certain Windows system files unique to the app no longer causes problems for users that are not assigned to the layer. (ALHEALP-1427)

  • On an image with EL running, you can select the remote admin share where OneDrive saves files without the machine failing with a blue screen. (ALHELP-1431)

  • When Elastic Layering is enabled on an image, a script that installs an application on the image now completes as expected. (ALHELP-1432)

Labs feature

Labs features are previews of potential functionality. While a feature is in Labs, do not use it in production. There is no guarantee that this feature will be included in the product, nor that it will work the same way if it is.

  • You can assign app layers as elastic layers on images that use a different OS layer: Elastic layer assignments normally require the App layer assigned uses the same OS layer that was used to create the App layer. You can try assigning an App layer as an Elastic layer on a layered image that uses a different OS layer.


    Issues can result from running an elastic layer on a different OS layer than the one used to create it.

To use a Labs feature, enable it in System settings.

Upgrade path

For the latest fixes and features, including compatibility with other software packages that you use, we encourage you to stay current with the App Layering upgrades.

You can upgrade from any App Layering release from 19.x to present.

App Layering 2106

June 2021

This release includes the following new feature:

  • An updated version of the OS Machine Tools. We recommend that you update your OS layers with the new tools now, so that you can use any new features that require them in the future.


  • After you finalize a platform layer, the machine no longer fails with a blue screen. (ALHELP-1177)

  • When Offload compositing is enabled and you set the default size of the elastic layering volume, the writable partition size is updated for all published images. (UNI-76795)

  • When logging in after adding elastic layers to an image, users no longer receive errors like the following (ALHELP-1445):

    “Critical Error: Your Start menu isn’t working. We’ll try to fix it the next time you sign in.”

    “Citrix App Layering - System Error: An unexpected system error occurred. Retry the operation or contact technical support.”

  • Files on an elastic layer no longer disappear and reappear under certain conditions. (ALHELP-1405)

  • When using FSLogix and OneDrive with elastic layers enabled, the VM can now access the user profile folder through the admin share (\\PCName\C$\Users). (ALHELP-1386, ALHELP-1405, ALHELP-1431)

  • FSLogix Profiles now work correctly when the app is installed on an app layer. (UNI-83092)

App Layering 2104

April 2021

This release includes the following improvements.


  • Synchronization of Layer version repair data now runs faster. (UNI-82197, ALHELP-1385)

  • The OfficeNoReReg.cmd script now updates existing values. (UNI-82088)

  • When accessing a published image running Windows 10 1909, you no longer receive the message, “The User Profile Service failed the sign-in. User profile cannot be loaded”. (ALHELP-1307)

  • After you install Crowdstrike, Edge launches on the first attempt. (ALHELP-1404)

  • When an image is running both elastic layering and Crowdstrike, Chrome and Microsoft Teams now launch on the first attempt. (ALHELP-1392)

  • If you install apps that have files with boot level components and Crowdstrike tags them, the apps no longer fail after you add a version to the layer. (ALHELP-1397)

App Layering 2102

February 2021

This release includes support for the following enhancement:

  • App Layering now runs on Google Cloud! You can:
    • Install an App Layering appliance on Google Cloud.
    • Create connector configurations for Google Cloud and Machine creation for Google Cloud.
    • Create layers on Google Cloud.
    • Move layers from a different platform to Google Cloud, using the Export and Import feature.
    • Publish layered images on Google Cloud, or to Machine creation running on Google Cloud.

This release also includes the improvements documented in fixed issues.


  • Apps published from an image template with elastic layering enabled now launch as expected. (ALHELP-1306, ALHELP-1315, UNI-81247)

  • When booting a session host with UEFI and Citrix Provisioning, the session no longer fails with a blue screen on the target device. (UNI-80889)

  • Compositing no longer fails because the CE runs out of available drive letters (ALHELP-1286, UNI-80179)

  • When an app is installed on a packaging machine, MSIEXEC.EXE no longer removes permissions on syswow64 content. (ALHELP-1327, UNI-81548)

  • WebEx no longer fails with Error 1407 when trying to uninstall it from a user layer. (ALHELP-1339, UNI-81434)

  • Apps in the Windows Start menu are listed in the correct section rather than in a section named ms-resource:AppName when user layers are enabled. (ALHELP-1323, UNI-81402)

  • Logging into the App Layering management console no longer results in a system error. (ALHELP-1332, UNI-81391)

  • VDAs no longer fail with a bluescreen on App Layering 20.11. (ALHELP-1337, UNI-82008)

  • The VDA is no longer unresponsive when users log in on to the VDA with elastic Layering enabled. (ALHELP-1369, UNI-81777)

  • Machine creation for vSphere connector no longer deletes files under UnideskCacheddisks on VMware. (ALHELP-1345, UNI-81662)

  • When assigned a user layer, you no longer get an error when accessing the Policy tab in Studio. (ALHELP-1355, UNI-81749)

App Layering 2011

November 2020

This release includes support for the following enhancement:

  • We now support Nutanix version 5.18.

  • You can use Windows 10, version 20H2 as an OS Layer in App Layering version 2011 or later. However, the following caveat applies.


    If you upgrade the OS layer to Windows 10 20H2 from an earlier release, upgrade directly to Build 19042.630, or above. Upgrading to builds of Windows 10 20H2 released before 11/16/2020 can result in inconsistent image deployments. For example, if you publish images using a template with Generalize Offline selected, the published images may not work correctly.


  • Windows 10, 2004 login times. An issue where Windows 10 2004 sometimes took 2–4 minutes to start, and occasionally included black-screens for 30-45 seconds has been fixed. (UNI-80656)
  • kmssetup script not added to the startup scripts folder. An issue that had prevented the kmssetup.cmd script from being added to the startup scripts folder when unzipped has been fixed. (ALHELP-1279, UNI-80410)
  • HP UPD driver not available as a printer driver. When you include an HP UPD driver in an app layer that becomes part of a published image, the driver is now available as a printer driver. The issue that prevented the driver from being listed has been fixed. (ALHELP-1278, UNI-80426)
  • Sessions hangs for minutes. An issue that had caused sessions to hang for minutes has been fixed. This issue had appeared after upgrading to App Layering 2005. (ALHELP-1263, UNI-80262)
  • User cannot reconnect to their desktop in App Layering 2009. An issue that caused random occasional blue screens when users tried to reconnect to their desktops has been fixed. (ALHELP-1317, UNI-81156)
  • When using the console on a 4K display, dialogue boxes open in top left corner. The issue that caused dialogue boxes to be displayed off center has been fixed. (ALHELP-1309,UNI-78951, UNI-78952)

App Layering 2009

September 2020

This release includes support for the following enhancement:

  • You can now override the default repository path and layer size for user layers by configuring Citrix Studio Policies.
  • The user interface for the App Layering management console has been updated with new Citrix branding images.

App Layering 2008

August 2020

This release includes support for the following features and enhancements:

  • Windows 10, 2004 support: Windows 10, 2004 is now supported as the OS for layered images. Using Windows 10, 2004 requires App Layering version 2008 or later. The required changes for this version of Windows 10 are not in previous App Layering releases.

  • Citrix Hypervisor 8.2 support We now support Citrix Hypervisor version 8.2.


App Layering 20.8.3 includes an important update to the included drivers. If you are using secure boot, you must upgrade to 20.8.3!

The 20.8.3 installation and upgrade packages are available for download. For new installations, download the Appliance Installation Package. For upgrades, download the Appliance Upgrade Package.


  • VM in vSphere with elastic layers enabled no longer fails after being deployed to a Citrix Provisioning server. An issue that had caused a VM in vSphere with elastic layers enabled to fail after being deployed to a Citrix Provisioning server was fixed. (ALHELP-1202, UNI-76300)
  • An issue that had caused the AutoDesk 2020 installer to fail in an app layer has been fixed. (ALHELP-476)
  • Users can now synchronize their OneDrive files without issues when On Demand syncing and Elastic layers are enabled (ALHELP-468)
  • Chrome extensions no longer cause the error message, “FAILED_TO_COPY_EXTENSION_FILE_TO_TEMP_DIRECTORY,” when elastic layers are enabled and an app layer is assigned. (ALHELP-419)

App Layering 2005

May 2020

The App Layering 2005 release includes support for the following features and enhancements:

  • Security enhancements: Security enhancements include cipher suite updates, third-party component upgrades, and runtime environment upgrades.

  • Secure boot support: Guest drivers are certified via Microsoft’s WHQL program. You can use certified guest drivers in secure boot configurations. (UNI-74917)

  • Customer user layer path: User layer files can now be stored in network shares whose locations are specified using custom paths. The custom paths can include environment variables. (UNI-78291)

  • Applications with services in user layer: When an application installed in a user layer contains Windows services, such as Google Chrome, those services are started as expected when the user logs in. (UNI-77660)

  • 2005 upgrade package: The App Layering 2005 upgrade package is large enough that older appliances cannot download it automatically. If you are running version 1911 or older, download the package manually from the downloads site. Also, we recommend running the upgrade from a management console in Secure HTTP (HTTPS). If you upgrade while in HTTP, messages do not display in the browser. If that happens, refresh the browser after 20 minutes. (Refreshing won’t cause issues despite the message that says not to refresh.) If the upgrade is still running, you get a “service unavailable error.” You can ignore that message and keep refreshing the browser every few minutes until the login page appears.


  • When using offload compositing with VMware vSphere, you can use layer names that start with square brackets [], as long as you follow the closing bracket with a space. For example, the name [OS] Windows 10 works, but the name [OS]Windows 10 hangs in vSphere studio and times out after about 40 minutes. (UNI-78452)

App Layering 2003

March 2020

This release includes the following:

  • We now support the following hypervisor, provisioning, and connection broker software versions:

    • Citrix Hypervisor 8.1
    • Nutanix AOS 5.16
  • When administrators configure a larger default user layer size, the disk will be automatically expanded the next time the user logs in.

  • When creating your OS layer in MS Hyper-V or VMware vSphere, you can now import the OS image, by using a script in the OS Machine Tools. The script imports the OS image right from the virtual machine, instead of using the management console and connector configuration. The script uses the Offload Compositing feature, which speeds up the import, and allows you to use a wider variety of virtual machines, including UEFI-based machines.


  • The Guest Layering service (ULayer) has been modified to not depend upon the Server service running on the end users’ virtual machines. (UNI-77242)
  • When delivered as an elastic layer, the Artiva application no longer fails when users attempt to log in. (UNI-76487)
  • An issue that had caused the StartCCMEXEC.cmd script to continually grow the log file, StartCCMExec.txt, even when CCMExec was not installed, has been fixed. To apply the fix, download the new OS Machine Tools folder for 20.3, and replace the StartCCMEXEC.cmd file with the new version. (UNI-77471)
  • When users install fonts on a user layer or elastic layer, the fonts persist the next time they log in. (UNI-63839)
  • When using a connector with Offload compositing enabled to publish an image, 8.3 file names are no longer incorrectly modified. (UNI-76961)
  • When adding a version to an app layer, you no longer receive the error “The Operation Failed due to a missing File. VMDK was not found.” (UNI-77702)
  • The issue with expiring JSON Web Tokens (JWT) when using the Offload Compositing feature in the connector configuration has been fixed. (UNI-76859)
  • The Hyper-V connector now reports the disk file size rather than its logical size, which was quickly filling up the cache. (UNI-76692)
  • Compatibility with Citrix Studio GPO policies when using images with user layers has been improved. (UNI-76918)

App Layering 2001

January 2020

This release includes the following:

  • We now support the following hypervisor, provisioning, and connection broker software versions:
    • Citrix Provisioning version 1912
    • Citrix Virtual Apps and Desktops version 7 1912
  • The following Windows 10 versions are now supported as an OS Layer:
    • Windows 10, version 1909
    • Windows 10, Enterprise Virtual Desktop edition (available from Microsoft in Azure only)
  • Our VMware vSphere connector now supports the VMware Paravirtual SCSI Controller. (UNI-75620)


  • In our App Layering appliance (ELM) deployment script for Azure, we have extended the expiration dates of signed Azure URLs pointing to standard repository disks. Make sure that you update your Azure deployment scripts from this release accordingly.
  • VDA installations no longer fail on a packaging machine. (UNI-76299)
  • When restarted, a layered image with a user layer no longer drops scheduler tasks. (UNI-77084)

App Layering 1911

November 2019

This release includes the following:

  • We now support the following hypervisor, provisioning, and connection broker software versions:
    • XenApp and XenDesktop 7.15 LTSR CU5
  • VMware vSphere:
    • Use the new Offload compositing option to significantly reduce the time it takes to package layers and publish images.
    • Select thin provisioned disks and UEFI (no secure boot with elastic layers and user layers) options.
    • Use the vSphere connector to package layers and publish images to VMware Cloud on AWS.


  • An error when finalizing OS layers with MBR partitions after a major Windows 10 upgrade has been fixed. (UNI-76210)
  • Compatibility with the Microsoft System Center Configuration Manager (SCCM) has been improved. (UNI-76198, UNI-76126, UNI-76129)
  • Users no longer lose their connection to a session host where FSLogix is running and elastic layering is enabled. (UNI-73793)
  • Rapid Reader 8.3 now starts as expected after being installed on a packaging machine. (UNI-76316)
  • IntelliJ IDEA Ultimate no longer freezes the desktop when the app is started. (UNI-76075)
  • Users no longer get a blue screen when they open SQL Management Studio and attempt to save a Query to OneDrive or a SharePoint folder. (UNI-76427)

App Layering 1910

October 2019

This release includes the following:

  • We support the following new versions of hypervisor, provisioning, and connection broker software:
    • Citrix Virtual Apps and Desktops version 7 1909
    • Citrix Provisioning version 1909
    • Nutanix Acropolis Hypervisor (AHV) version 5.11
    • VMware Horizon View 7.9
  • On the Hyper-V platform, you can package layers and publish images using Offload Compositing to dramatically improve performance and compatibility. Gen2 VMs and VHDX disk format are now supported.

  • The App Layering Agent has been updated to support the new Offload Compositing feature. If you use the agent in your deployment, we strongly recommend that you install the agent update on any servers where it is installed.

  • Windows Search index performance is improved when using full User Layers.

  • For administrators publishing layered images, this version adds validation and warnings to give guidance on what disk size to use based on selected app layers.


  • A PVS Support article that called for removal of the CDF Driver Registry entry has been updated to fix issues troubleshooting Profile Management. (UNI-75720)
  • The issue where Defender didn’t update correctly has been fixed. (UNI-74918)
  • Windows Search Service starts as expected on a packaging machine when using a caching connector. (UNI-75915)
  • Windows Defender now starts successfully on an app layer created from a Windows 1809 OS layer. (UNI-74997)
  • Users can now sync their OneDrive files when On Demand syncing and elastic layers are enabled. (UNI-74618)
  • OneDrive’s on-demand feature now streams files correctly when elastic layering is enabled. (UNI-73121)
  • User layer repairs now complete successfully when the minimum recommended permissions are set on the Users\ path. (UNI-75552)
  • When installing a Chrome extension with user layers enabled and an app layer assigned as an elastic layer, you no longer receive the error Can not install package: FAILED_TO_COPY_EXTENSION_FILE_TO_TEMP_DIRECTORY (UNI-75568)
  • Windows Search index performance has been improved when using full user layers. (UNI-73049)
  • This release adds validation and warnings about what disk size you can use. The guidance is based on your configuration and the app layers selected. (UNI-54390)

App Layering 1908

August 2019

This release includes support for these new features and improvements.

  • Windows versions: Windows 10 version 1903 is now supported as an OS Layer.

  • Connection brokers: We now support the following connection broker software version:
    • VMware Horizon View 7.9
  • User layer repair: You can now manually repair user layers so that all files and registry settings coming from a specific set of app layers can be made visible again.


  • Hyper-V connector PowerShell sessions no longer expire when a file copy takes longer than 30 minutes. (UNI-74283, UNI-74292)

  • The issue where System and Display properties did not open correctly when user layers were enabled has been fixed. (UNI-74547)

  • Removing store apps from a Windows 10 OS layer no longer causes features, like Settings and Display Properties, to malfunction. (UNI-74852)

  • The Windows Defender update KB4052623, now successfully installs and works for user layer-enabled users. (UNI-74942)

Contact Citrix

We welcome your feedback about this release.

  • Use our online Forum to speak directly with Citrix employees and other organizations deploying Citrix App Layering.
  • For product issues and questions, open a Support Case.

We look forward to hearing what you think about App Layering.