A Terminal Services client may be unable to connect to a Terminal Services license server that is installed on a Windows Server 2003-based computer

A Terminal Services client may be unable to connect to a Terminal Services license server that is installed on a Microsoft Windows Server 2003-based computer.

This problem occurs if the following conditions are true:

• You use a backup program that uses the Volume Shadow Copy Service (VSS).
• The Terminal Server Licensing administrative tool contains expired Terminal Server client access licenses (CALs).
• The Terminal Services licensing pool is empty.

This problem occurs because the thread that recovers the expired CALs from the Terminal Server license server does not restart when the Volume Shadow Copy Service finishes the backup process.

To work around this problem, use one of the following methods:

• Restart the Terminal Server Licensing service after you run the backup program.
• Configure a script to restart the Terminal Server Licensing service every 24 to 72 hours.

Note When you restart the computer, the Terminal Server Licensing service also restarts. Therefore, if you restart the computer regularly, you are unlikely to experience this problem.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

The Terminal Server Licensing service works with VSS. When you use VSS to back up a program, you do not have to restart it. VSS temporarily suspends any part of the program that interferes with the backup process.

When the backup program sends a backup request, VSS informs the program that is being backed up. Then, this program temporarily flushes unsaved data from memory. This process guarantees that the data stays consistent. The program then suspends operations. When the backup finishes, VSS informs the program that it can resume operations.

For more information about VSS, visit the following Microsoft Web sites: