Known issues and considerations

The following issues have been identified in the current release.

App Layering appliance and management console

  • When accessing the App Layering appliance using Internet Explorer running on a server OS, the fonts for the management console might not load correctly. To prevent this issue, add the appliance IP address to the Trusted Sites list in Internet Explorer. (UNI-50830)
  • When installing the App Layering appliance, you must use the default CPU setting of 4 CPUs.
  • If you are using Roles in a large, complex Active Directory environment and logins are slow, make sure that all Roles have been assigned to explicit users, rather than to groups.

App Layering OS Machine Tools (Release 19.5 or later)

  • After upgrading to 19.5 or later from 19.3 or earlier release, when you prepare your OS image for layering in release 19.5, you must download and run the App Layering OS Machine Tools from this release. Otherwise, your KMS Office Activation will not be updated to use Office 2019.

App Layering OS Machine Tools (Release 19.1 only)

  • When preparing your OS image for layering in release 19.1, you must download and run the App Layering OS Machine Tools from Release 18.12. Otherwise, your KMS Office Activation will not be triggered at desktop startup.

Elastic Layering

  • Microsoft Office cannot be elastically layered due to the way its licenses are integrated with the Windows Store. The Office app layer must be included in the Layered image.
  • When you enable an image with elastic layering, users might be able to view files and directories from other sessions in Windows Explorer. Directories explored in the other session might create folders visible to all sessions that have permission to browse that directory.
  • If you use elastic layer assignments with Windows Server 2008 or Windows 7, create your file share with a sector size of 512. For details about this issue and related operating system updates, see the following:
  • When using Elastic Layer Assignments, Persona Management in Horizon View is not supported. Although Citrix App Layering supports Horizon View 6.1 and later, Elastic Layer Assignments do not support these versions of View Persona Management. (UNI-53639)
  • When Elastic Layering is enabled, Windows 10 users may see errors when launching a small set of UWP apps that are bridge apps. These apps fail to launch and cannot be used. (UNI-71062)

User layers

  • Signing on after upgrade starts the Windows First Sign-in screens: After upgrading to 4.10 or later, signing on starts the Windows First Sign-in screens. This is a normal windows process during upgrades. Your User layer is brought up to date with the OS version, and no User layer files are lost in the process.
  • When User layers are enabled, MSI installers are blocked from running on provisioned desktops at system startup - This is because the Layering service must be running before the MSI file can run, and the Layering service doesn’t run until a user logs in. If an MSI attempts to run, you get this error:

    “The Windows Installer service depends on the Citrix App Layering Guest Service service which failed to start because of the following error:The service cannot be started, either because it is disabled or because it has no enabled devices associated with it.”

Windows 10 support

  • Windows 10 upgrades require a 60-GB disk for the OS layer version: When you add a version to the Windows 10 OS layer, change the maximum layer size from 30 GB to 60 GB.(UNI-52422)
  • Upgrading requires extra steps when going to a new Windows 10 major release: During the upgrade, Windows 10 can create a recovery volume on the same disk as the OS layer version. Always delete this volume before you finalize the OS layer version. Otherwise, the recovery volume can cause desktops to fail to start correctly. For more information, see App Layering: Windows 10 upgrade may result in new recovery volume partition.
  • On Windows Server 2012, if you want to use Windows Store apps and you are using the included OS Optimization Script as part of preparing the OS image, you can enable Store apps by turning on Windows Updates. (UNI-67195)


  • When using the Windows mini-boot disk option, you can specify up to four Prerequisite layers for any given App layer. If an application requires more than four other applications to be present during installation, you can install multiple applications on any or all of the layers. The limit is on the number of layers, rather than on the number of applications. (UNI-69524)

Citrix Provisioning

  • When you create an image template, the target device hardware settings must match the Windows operating system and platform layer settings. Ensure that the hardware settings on the target device match the operating system and platform layer hardware settings, especially the number of CPUs. If the settings don’t match, you can get a restart required message when you start the published image. (UNI-50799)
  • If you use Provisioning Services, you must disable IPv6 in the OS layer and not in the Platform layer. (UNI-53600)

Citrix Hypervisor

  • When you prepare your operating system image for use in Citrix Hypervisor, you must open port 5900 to allow console access. (UNI-50846)
  • A Citrix App Layering connector configuration should always point to the master node. (UNI-52454)
  • If an App layer machine is hung and spinning at boot, one of the layer disks may not have been attached. This can happen if a prerequisite layer is selected and the Xen Guest Tools are not included in either the OS or Platform layers.
  • If you receive the following message when creating an App layer, it is because a Platform layer is specified in the App layer settings. Platform layers do not work with the App layering’s performance enhancing caching feature. (UNI-67741) image

  • If you are using Prerequisite layers when creating either the OS layer or the Platform layer, Xen Tools must be present during layer creation. Without the tools, the packaging machine blue screens because Citrix Hypervisor isn’t able to see any devices that are attached after the DVD drive, and the DVD drive is always in the 3rd slot. (UNI-67741)

Nutanix Acropolis

  • If you receive the following message when creating an App layer, it is because a Platform layer is specified in the App layer settings. Platform layers do not work with the App layer’s performance enhancing caching feature. (UNI-67742)


VMware Horizon View

  • Elastic layers are only supported with floating desktop pools. (UNI-53442)
  • When creating a Windows 10 or Windows Server 2016 virtual machine on VMware version 6.7, the virtual machine’s boot options default to Unified Extensible Firmware Interface (UEFI) firmware. However, UEFI virtual machines are not supported at this time with Citrix App Layering. Please use BIOS setting instead. (UNI-69435)

Microsoft Azure

  • Citrix App Layering does not support Azure File storage. Create a network file share or an SMB file share in Azure to use with Citrix App Layering. (UNI-42272)
  • Managed disks are not supported. When creating a virtual machine in Azure, be sure to select No managed disks.

Microsoft Hyper-V

  • When using a Hyper-V connector configuration, you cannot store disks on a remote share instead of local storage. Currently, putting a remote path like \\<server>\<share> fails validation even if the user account specified in the connector configuration has permission to access the share. (UNI-74243)
  • When you configure Elastic Layering in Hyper-V, you must use unmanaged RDS pools (UNI-53545)
  • If you receive the following message when creating an App layer, it is because a Platform layer is specified in the App layer settings. Platform layers do not work with the App layering’s performance enhancing caching feature. (UNI-71868, UNI-67743)


  • When creating an OS layer on Hyper-V Server 2019 you may receive the error:

    ‘Failed to create new VHD. Make sure there is enough space on the share specified in the connector configuration.’

    This error is due to an issue with the Microsoft Powershell New-VHD cmdlet. We are keeping our eye out for a fix from Microsoft. In the meantime, please use following workaround for this error:

    1. Make sure the Gold VM has no checkpoints.
    2. Make sure the Gold VMs disk is in the same directory path that is configured in the connector config. Example: Local path is D:\Brock\ Gold VM disk is stored in D:\Brock\WIn10Gold\Win10GoldDisk.vhdx