SSH Prefix Truncation Vulnerability (Terrapin attack) on Citrix Applayering

SSH Prefix Truncation Vulnerability Terrapin attack on Citrix App Layering . Note: The Terrapin attack can reduce the security of SSH by using a downgrade attack via man-in-the-middle interception. The attack works by prefix truncation; the injection and deletion of messages during feature...

Citrix App Layering 2409 - Unable to Edit App Layers with Boot Error 0xc000000f

Administrators may encounter an issue where they are unable to edit Application Layers within Citrix Elastic Layer Management ELM version 2409 after applying the February 2025 patches to their Windows 11 24H2 packaging machines. This inability to edit App Layers is accompanied by aboot error code...

Citrix App layering 24.3 | Hidden RPC Services Vulnerabilities reported on ELM Appliance

Vulnerability scanning software may flag "Hidden RPC Services Vulnerability" on Citrix App layering ELM Appliance...

Citrix App Layering - Error "Cannot convert undefined or null to object"

Unable to import layers from a remote share. While attempting to connect to a share, we see the error "Cannot convert undefined or null to object". The error message is displayed after about 10 mins...

Publishing an App Layering image to PVS with Offload Compositing may fail

When publishing an App Layering image to PVS using Offload Composting, it may fail...

New Teams Deployment Guidance for App Layering or User Personalization Layer(UPL)

Microsoft Teams 2.x has changed its installation method and now installs under C:\Program Files\WindowsApps. Based on those changes this article provides the specific steps for the deployment of the Teams 2.x in an App LayeringAL or User Personalization LayerUPL environment. For the most current...

M365 activation fails when app layering elastic\user layers are enabled

When publishing an App Layering image with Elastic enabled, M365 may fail to be licensed. You may find the license is missing at C:\ProgramData\Microsoft\Office\Licenses\5...

BITS performance counters not working after publishing App Layering image to PVS

When you published an image from App Layering to PVS, Target Devices may not show BITS performance counters...

App Layering - Changes to Scheduled Tasks do not show up on the layered image

Making changes to an existing scheduled task will not be reflected on the published image. Adding a version to the layer shows the old values and not the changes...

Increase the size of the App Layering boot disk for packaging

When you create/edit layers in App Layering, a packaging machine is created. If you have caching enabled, then a boot disk is created as well as copies of the OS layer and any relevant App Layer. When the packing machine is booted, some system data such as the pagefile is stored on that boot disk...

App Layering - Support for VHDX format for User layers

This article describes the supported format VHD or VHDX for User layers...

Installing Teams 2.x in an App Layering

Teams will not work properly in an image if it was installed in an App Layer using any version for App Layering prior to 2403.2...

How to change the ELM disk from unmanaged to managed on Microsoft Azure

This article will provide you with the steps required to change the ELM disk from unmanaged to managed using Microsoft Azure and Citrix App Layering...

App Layering - Unable to publish the image - disk space is full

App Layering - Unable to publish the images with a disk space is full error message. Error: A failure occurred while publishing the Layered Image: An error occurred while compositing the layer or image. Please check the available disk space on the local storage or the size of the target image...

How to configure ARM templates using the new Azure App Layering Azure connector

How to configure ARM templates using the new Azure App Layering Azure connector...

App Layering - Windows and Office activation lost after upgrading to 2211

Provisioned machines with user layers lose their Windows activation status or Office will report not being activated, after upgrading to App Layering 2211...

App Layering - PVS Connector with Offload Enabled - Task Error "404 (Not Found)"

App Layering PVS connector with offload enabled "An unexpected system error occurred. Retry the operation or contact technical support. Exception Message: Response status code does not indicate success: 404 Not Found"...

How to export logs using App Layering 2204 or higher

Walk-through the new export logs steps...

App Layering - Stuck Tasks or new tasks hang at "pending" or "stalled"

Tasks won't progress, appear as stalled. New tasks sit at "Pending" From maservice.log: 2021-01-11 09:10:25,575 WARN 20193 UnitOfWorkImplemen: Transaction is implicitly being rolled back at Uni.Appliance.PersistenceLayer.UnitOfWork.UnitOfWorkImplementation.Dispose 0x00025 in :0 at...

App Layering - 2206 WMI applications relying on the Global Assembly Cache (GAC) fail to run.

WMI applications no longer work after upgrading to App Layering 2206. Specifically anything that uses the GACMSIL directory...