Share via

Event ID 45 — Remote Desktop Services Client Access License (RDS CAL) Availability

  • Article

Applies To: Windows Server 2008 R2

When a client—either a user or a device—connects to a Remote Destkop Session Host server, the RD Session Host server determines if a Remote Desktop Services client access license (RDS CAL) is needed. The RD Session Host server then requests an RDS CAL from a Remote Desktop license server on behalf of the client attempting to connect to the RD Session Host server. If an appropriate RDS CAL is available from a license server, the RDS CAL is issued to the client, and the client will be able to connect to the RD Session Host server.

RDS CALs are installed onto a license server by using the Remote Desktop Licensing Manager tool.

Event Details

Product: Windows Operating System
ID: 45
Source: Microsoft-Windows-TerminalServices-Licensing
Version: 6.1
Symbolic Name: TLS_E_SERVERTOSERVER
Message: The Remote Desktop license server cannot communicate with another Remote Desktop license server because of the following error: %1!s!.

Resolve

Check firewall settings, and if necessary, identify and fix network connectivity issues

To resolve this issue, check firewall settings to ensure that remote procedure call (RPC) communication is not blocked between the Remote Desktop license server and other license servers. If the firewall settings are correctly configured or the problem persists, identify and fix network connectivity issues.

Note: License servers maintain information about the location of other accessible license servers, and whether those license servers have Remote Desktop Services client access licenses (RDS CALs). In certain cases, license servers will notify each other when RDS CALs are added to their databases, or when they have no remaining RDS CALs to issue. To notify each other, there must be network connectivity between the license servers.

To perform these tasks, refer to the following sections.

Check firewall settings

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

To check firewall settings:

  1. On the license server, click Start, and then click Control Panel.
  2. Click Security, click Windows Firewall, and then click Change Settings.
  3. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Yes.
  4. In the Windows Firewall Settings dialog box, click the Exceptions tab.
  5. Under Program or port, ensure that the Remote Desktop Licensing Server check box is selected. If the Remote Desktop Licensing Server check box is not selected, select it, and then click OK.
  6. On the other license servers, click Start, and then click Control Panel.
  7. Click Security, and then click Windows Firewall.
  8. Click Change Settings, and then, in the Windows Firewall Settings dialog box, click the Exceptions tab.
  9. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Yes.
  10. Under Program or port, ensure that the Remote Desktop Licensing Server check box is selected. If the Remote Desktop Licensing Server check box is not selected, select it, and then click OK.

Note:  To view more detailed information about Windows Firewall settings, use the Windows Firewall with Advanced Security snap-in.

Identify and fix network connectivity issues

To identify and fix any network connectivity problems between the license server and other license servers, do the following:

  • Determine if there is a network connectivity problem by using the ping command.
  • Perform additional troubleshooting steps, if necessary, to help identify the cause of the problem.

To perform these tasks, refer to the following sections.

Note:  The following procedures include steps for using the ping command to perform troubleshooting. Therefore, before performing these steps, check whether the firewall or Internet Protocol security (IPsec) settings on your network allow Internet Control Message Protocol (ICMP) traffic. ICMP is the TCP/IP protocol that is used by the ping command.

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

Determine if there is a network connectivity problem

To determine if there is a network connectivity problem between the license server and the other license servers:

  1. On the license server, click Start, click Run, type cmd, and then click OK.

  2. At the command prompt, type ping server_FQDN, where server_FQDN is the fully qualified domain name (FQDN) of another license server (for example, server1.contoso.com), and then press ENTER.

    If the ping was successful, you will receive a reply similar to the following:

    Reply from IP_address: bytes=32 time=3ms TTL=59

    Reply from IP_address: bytes=32 time=20ms TTL=59

    Reply from IP_address: bytes=32 time=3ms TTL=59

    Reply from IP_address: bytes=32 time=6ms TTL=59

  3. At the command prompt, type ping IP_address, where IP_address is the IP address of another license server, and then press ENTER.

If you can successfully ping another license server by IP address, but not by FQDN, this indicates a possible issue with DNS host name resolution.

If you cannot successfully ping another license server by IP address, this indicates a possible issue with network connectivity, firewall configuration, or IPsec configuration.

Perform additional troubleshooting steps

The following are some additional troubleshooting steps that you can perform to help identify the root cause of the problem:

  • Ping other computers on the network to help determine the extent of the network connectivity issue.
  • If you can ping other servers but not the other license servers, try to ping the other license servers from another computer. If you cannot ping the other license servers from any computer, first ensure that the other license servers are running. If the other license servers are running, check the network settings on the other license servers.
  • Check the TCP/IP settings on the local computer by doing the following:
    1. Click Start, click Run, type cmd, and then click OK.
    2. At the command prompt, type ipconfig /all, and then press ENTER. Make sure that the information listed is correct.
    3. Type ping localhost to verify that TCP/IP is installed and correctly configured on the local computer. If the ping is unsuccessful, this may indicate a corrupt TCP/IP stack or a problem with your network adapter.
    4. Type ping IP_address, where IP_address is the IP address assigned to the computer. If you can ping the localhost address but not the local address, there may be an issue with the routing table or with the network adapter driver.
    5. Type ping DNS_server, where DNS_server is the IP address assigned to the DNS server. If there is more than one DNS server on your network, you should ping each one. If you cannot ping the DNS servers, this indicates a potential problem with the DNS servers, or with the network between the computer and the DNS servers.
    6. If the other license servers are on a different subnet, try to ping the default gateway. If you cannot ping the default gateway, this might indicate a problem with the network adapter, the router or gateway device, cabling, or other connectivity hardware.
  • In Device Manager, check the status of the network adapter. To open Device Manager, click Start, click Run, type devmgmt.msc, and then click OK.
  • Check network connectivity indicator lights on the computer and at the hub or router. Check network cabling.
  • Check firewall settings by using the Windows Firewall with Advanced Security snap-in.
  • Check IPsec settings by using the IP Security Policy Management snap-in.

Verify

To verify that Remote Desktop Services client access licenses (RDS CALs) are installed and available on the Remote Desktop license server, use the Remote Desktop Licensing Manager tool.

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

To verify that RDS CALs are installed and available:

  1. On the license server, open Remote Desktop Licensing Manager. To open Remote Desktop Licensing Manager, click Start, point to Administrative Tools, point to Remote Desktop Services, and then click Remote Desktop Licensing Manager.
  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, expand All Servers, and then click the license server. In the right pane, the type, version, and number of RDS CALs installed on the license server is listed.

Note:  To verify that the Remote Desktop Session Host server can contact a Remote Desktop license server with the appropriate type of RDS CALs, use Licensing Diagnosis in the Remote Desktop Session Host Configuration tool on the RD Session Host server.

Remote Desktop Services Client Access License (RDS CAL) Availability

Remote Desktop Services