QlikView server communication interruptions following Microsoft Windows RC4 cipher suite deprecation

[Ray_Strother]

Beginning on April 14, 2026, QlikView customers experienced outages and intermittent disruptions within their QlikView environments. These incidents coincided with the deployment of Microsoft’s April 2026 security patches to Domain Controllers, which affected QlikView Server Service (QVS) communications over port 4747.

The Microsoft patches introduced changes targeting Kerberos authentication and RC4 encryption. As a result, QlikView environments where RC4 remained enabled (such as at the domain account or Windows server level) became unstable or non-functional.

The impact on QlikView may include, but is not limited to:

• Failed QlikView Distribution Server distribution tasks with an error code indicating an Authentication Failure.
• "No Server" message on the QlikView AccessPoint with an error message in the Web server log indicating that the Web server cannot connect to the QlikView Server.
• Failed Qlik NPrinting distributions to QlikView using a QVP Connection.
• Problems accessing the QlikView Server settings from the QlikView Management Console, or failures for the QlikView Server to come online after a restart.

This article documents the steps to reconfigure the environment to comply with the RC4 cipher suite deprecation. 

Resolution

Information in this article is based on Microsoft's remediation steps and has been adjusted and expanded to include QlikView-specific instructions. For the original, see Detect and remediate RC4 usage in Kerberos | learn.microfot.com. 

There are three stages; not all may be required. Always start at the first one.

Reset the Computer Account

These steps require you to remove the computer from the domain and then re-add it. Before proceeding, ensure you have a Local Administrator account and its password for each of the QlikView servers.

1. Confirm the Domain Controllers and the QlikView server(s) have the Microsoft patch applied.
2. Reset the Active Directory Computer Account (not the Service Account) on the Domain Controller’s Active Directory Users and Computers interface.
3. Place the QlikView server(s) into a Workgroup:
   1. Log onto the local computer of the QlikView server
   2. Open the Server Manager
   3. Go to Local Server
   4. Go to Computer Name
   5. Place the server in a local group
   6. Reboot the QlikView server
   7. Repeat the step for all QlikView servers if you have additional nodes
4. Return the QlikView server(s) to the Domain:
   1. After the reboot, return to the Server Manager
   2. Go to Local Server
   3. Go to Computer Name
   4. Re-join the Domain and reboot the server
   5. Repeat the step for all QlikView servers if you have additional nodes
5. Test the QlikView environment to confirm this has resolved the interruptions.

Kerberos ticket reset

It may be necessary to clear the Kerberos ticket on the affected QlikView server(s).

1. Open PowerShell or a Command Prompt with elevated permissions
2. Run the command: Klist purge

Reset the Service Account

It may be necessary to reset the Domain password for the QlikView service account.

1. Verify that all server Domain Controllers and Windows Servers on which the QlikView Application is installed are patched.
2. Verify that RC4 encryption is disabled.
3. Reset the QlikView service account password.
4. Open the Services panel, then reapply the QlikView service account using the new password
5. Restart the QlikView services.

   If the QlikView service account was used for any data connection(s), they will need to be updated with the new password.

Related Content

• What Changed in RC4 with the January 2026 Windows Update and Why it is Important | techcommunity.mic... 

Microsoft Patches:

• Windows Server 2022 (DC): KB5082142
• Windows Server 2019 (DC): KB5082123
• Windows Server 2016 (DC): KB508208

Environment

• QlikView