Section 10.6. Installing an Application

10.6. Installing an Application

If you want to install an application on the terminal server that is in Terminal Services mode so that users can access it from thin clients, the proper way is to install the application through the Add/Remove Programs applet inside the Control Panel and not through the application's default installation method. By using the Add/Remove Programs applet, Windows ensures that program files are installed to the Windows root directory on the server, as opposed to the Windows subfolder under the user's home directory. Windows also ensures the programs are installed properly for multiple use of the same memory space. Both of these steps make the programs available for multi-session access. Any program that displays the Certified for Windows logo will be able to handle the differences between normal local access and usage in a Terminal Services scenario. Other applications can cause problems, so be sure to test each application before deployment.

Also, it's prudent to check for prewritten scripts that help ensure an application is installed properly for multi-user execution. Microsoft tests some common applications for compatibility and releases templates and modifications so that these programs will install correctly for use with Terminal Services. You can find these scripts in %SystemRoot%\Application Compatibility Scripts\Install.

Installing programs on the terminal server machine using RDC (for remote administration) works like any other software installation program, although depending on the application it might work only under the remote administration terminal and not other users' sessions.

To install a program using the Add/Remove Programs tool, follow these steps:

1. Open the Add/Remove Programs applet inside the Control Panel.

2. From the left bar, choose Add New Programs.

3. Click CD Or Floppy, which will raise a wizard. Click Next to continue.

4. Insert the program distribution media if it's external. Windows will attempt to look in your drives for a setup file. If Windows can't find the file, it will prompt you for its location. Click Next to complete this step.

5. Windows will begin the installation, but it will leave the After Installation dialog box open. Do not close that window until the installation is finished; otherwise, the program will not function correctly. Also, do not reboot the computer if the program's setup utility asks you to restart.

6. After the installation has completed, but before any necessary reboot, click Next in the After Installation dialog box and let Windows detect the changes and record the necessary data. Finally, click Finish.

7. Reboot at this point only if the setup program required it earlier.

Alternatively, you can go to the command line and use the change user command, which cycles through what Windows Server 2003 terms install modes and execute modes using switches attached to the command. Let's look at that in a bit more detail.

Executing change user /install before installing a new application places the system in install mode. Install mode also suspends .ini file mapping, which Windows normally uses to match .ini files to programs that use them and the associated users that actually install the program. The system also notes the way the setup routine initially installs the program. Running change user /execute when the installation finishes reverts the system to execute mode, reactivates .ini file mapping, and propagates specific data for each user to their respective home directories. In addition, when the user opens the program, user-specific registry setting files (.ini, .dll, .ocx, and so on) are propagated as needed to the user's home directory.

So, in brief, follow these steps from the command line to manually install a program:

1. Before installing a program, run change user /install from the command line.

2. Then, install the program using the application's native setup routine.

3. When installation is complete, run change user /execute to finish the process.

Once you have begun installing programs for use on a terminal server machine, do not uninstall Terminal Services. The programs installed while Terminal Services was running might not function correctly at that point. If this happens, the easiest way to start over is with a clean slate: reformat the computer and reinstall the operating system.