Following up on the issue βRemote Assistance canβt make the connectionβ, as already mentioned in last weekβs KB, the root cause has now been clearly identified.
The problem is related to recent Microsoft updates released for Windows 11, which address the security vulnerability CVE-2026-20824.
More specifically, the issue is documented in the following KB:
Note: The solution to this issue is described at the end of this post.
When Does the Issue Occur?
A key point to understand is that the issue is triggered if the updates are installed on either side of the Remote Assistance session:
- The target machine (the device receiving assistance)
- The operator machine (the device providing assistance)
Β This means that even if your VDI environment is not patched, the error will still occur if the support operator is using a Windows 11 machine updated after January 2026.
The result is the well-known error:
Expected Fix
A permanent fix is expected to be released soon with Omnissa Horizon version 2603 (I hope
)
Current Workaround
At the moment, if you want to provide Remote Assistance without removing Windows updates, you must follow a manual (and somewhat cumbersome) process.
Steps for the End User (Receiving Assistance)
- Click on the Start (Windows) button
- Search for and open Remote Assistance
- Select “Invite someone you trust to help you”
- Click “Save this invitation as a file”
- Save the file and share it with the support operator
- A security code will be displayed β share this code as well
Steps for the Support Operator
- Open the received invitation file
- Enter the provided security code
- Click OK
Final Step
- The end user will receive a prompt to approve the connection
- Once approved, the Remote Assistance session will start
Final Considerations
This workaround allows you to continue providing support without uninstalling security updates, but it is clearly less efficient compared to the standard workflow within the Horizon console.
Until the official fix is released, it is important to:
- Inform support teams about the behaviour
- Adjust troubleshooting procedures accordingly
- Plan for the upcoming Horizon upgrade
Update (April 2026)
The issue described in this article regarding Remote Assistance after the January 2026 Windows updates has been resolved starting from Horizon Agent 2603, with the introduction of a specific registry key.
β Solution for Horizon Agent 2603 and later
With Horizon Agent 2603, the issue can be resolved by configuring the following registry key:
HKLM\SOFTWARE\Omnissa\Horizon\RemoteAssistance\fEnableLHTicket
STRING with value set to 1
This key enables a new Remote Assistance user experience, changing the behaviour compared to previous versions.
π§βπ» New user experience
When this setting is enabled:
- The Remote Assistance session follows a more modern workflow aligned with recent Microsoft security changes
- End users receive clearer and more contextual notifications
- Compatibility with the latest Windows security updates is ensured
With the key modified, when a Remote Assistance session is initiated, the VDI user will see a code displayed on their screen (similar to the image below) that they must communicate to the operator to allow the operator to connect.
Versions before 2603
For Horizon Agent versions earlier than 2603, the registry key is not available by default.
In this case:
- You must open a support request with Omnissa
- Support can provide a specific/custom Agent build
- Only with that version will it be possible to enable the registry key
Recommendations
-
- Plan to upgrade to Horizon Agent 2603 or later whenever possible
- Validate the registry configuration within your environment before production rollout
- Test the new user experience to understand the behavioral changes