Event ID 1043 — Remote Desktop Services Client Access License (RDS CAL) Availability

Applies To: Windows Server 2008 R2

An RD Session Host server must be able to contact a Remote Desktop license server to request Remote Desktop Services client access licenses (RDS CALs) for users or computing devices that are connecting to the RD Session Host server. In addition, the Remote Desktop licensing mode configured on an RD Session Host server must match the type of RDS CALs available on the license server.

Event Details

Product: Windows Operating System
ID: 1043
Source: Microsoft-Windows-TerminalServices-RemoteConnectionManager
Version: 6.1
Symbolic Name: EVENT_LICENSE_SERVER_AUTHENTICATION_FAILED
Message: The Remote Desktop Session Host server cannot communicate with the Remote Desktop license server %1. Ensure that the computer account for the Remote Desktop Session Host server is a member of the Terminal Server Computers group on the license server.

Resolve

Add the Remote Desktop Session Host server to the Terminal Server Computers local group on the Remote Desktop license server

To resolve this issue, add the computer account for the RD Session Host server to the Terminal Server Computers local group on the Remote Desktop license server.

Note:  When the License server security group Group Policy setting is enabled and applied to a license server, the license server will respond only to license requests from RD Session Host servers whose computer accounts are members of the Terminal Server Computers local group. This Group Policy setting is located in Computer Configuration\Administrative Templates\Windows Components\Remote Desktop Services\RD Licensing.

To perform this procedure, you must have membership in the local Administrators group, or you must have been delegated the appropriate authority.

To add the computer account for the RD Session Host server to the Terminal Server Computers group:

  1. On the license server, open the Local Users and Groups snap-in. To open Local Users and Groups, click Start, click Run, type lusrmgr.msc, and then click OK.
  2. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Continue.
  3. In the left pane, click Groups.
  4. In the right pane, right-click the Terminal Server Computers group, and then click Properties.
  5. Click Add.
  6. In the Select Users, Computers, or Groups dialog box, click Object Types.
  7. Select the Computers check box, and then click OK.
  8. Locate and then add the computer account for the RD Session Host server that you want to add.
  9. Click OK to close the Select Users, Computers, or Groups dialog box, and then click OK to close the Terminal Server Computers Properties dialog box.

Note:  If the license server is installed on an Active Directory domain controller, use the Active Directory Users and Computers snap-in to create the Terminal Server Computers group. To create the Terminal Server Computers group on a domain controller, you must have membership in the Domain Admins group in AD DS, or you must have been delegated the appropriate authority. To open Active Directory Users and Computers, click Start, click Run, type dsa.msc, and then click OK.

Verify

To verify that the RD Session Host server can contact a Remote Desktop license server with the appropriate type of Remote Desktop Services client access licenses (RDS CALs), use Licensing Diagnosis in Remote Desktop Session Host Configuration.

To perform this procedure, you must have membership in the local Administrators group, or you must have been delegated the appropriate authority.

To use Licensing Diagnosis in Remote Desktop Session Host Configuration:

  1. On the RD Session Host server, open Remote Desktop Session Host Configuration. To open Remote Desktop Session Host Configuration, click Start, point to Administrative Tools, point to Remote Desktop Services, and then click Remote Desktop Session Host Configuration.
  2. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Yes.
  3. In the left pane, click Licensing Diagnosis.
  4. Under Remote Desktop Session Host Server Configuration Details, the value for Number of RDS CALs available for clients should be greater than 0.

Remote Desktop Services Client Access License (RDS CAL) Availability

Remote Desktop Services