To properly terminate usage tracking of a thin-client application, users need to use the application's Exit feature (for example, File menu > Exit) rather than clicking the Close button in the upper-right corner of the session window. Using Exit correctly exits the application, logs the user out of the session, and terminates usage tracking.
If, rather than using the application's Exit feature, the user closes the terminal server session (by clicking the Close button in the upper-right corner of the session window), the user is disconnected from the session but not logged out. The session remains open on the terminal server, and the user can reconnect to the same session by launching the application again. This means that the application was never really exited, so usage tracking continues.
To ensure that disconnected sessions are closed out, you can configure the terminal server to end disconnected sessions after a certain period of time. For instructions, see your terminal server documentation.
If you are using ZENworks for Desktops, you can enable a Terminal Server policy (on a User package) and apply the User package to the appropriate users. The Terminal Server policy should configure a timeout interval for disconnected sessions (Disconnection Timeout setting) and reset the connection on timed-out sessions (Reset Broken or Timed-Out Sessions setting). For more information, see the ZENworks for Desktops 3.2 documentation.