Installing : Installing SA and SA XT on same machine : Uninstalling System Architect XT
  
Uninstalling System Architect XT
The installation process for either product works the same as if only one of them were installed. In other words, each product is listed in the Add or Remove Programs dialog of the Windows Control Panel. However, you should consider the following factors when you uninstall System Architect or System Architect XT when both are installed in the same computer:
If you attempt to uninstall only System Architect, System Architect XT will cease to work properly because common files are deleted. In this scenario, you can continue to uninstall System Architect, but you are advised that you should also System Architect XT.
When you uninstall System Architect XT, no special information is provided. Even though common files are also deleted in this instance, System Architect will reinstall those files the next time it is started. This is the standard behavior whenever System Architect files are deleted.
When you need to uninstall both System Architect and System Architect XT from the same computer, the sequence you should follow is to uninstall System Architect XT first, and System Architect second. If you do not follow this recommended sequence, and uninstall the products in the reverse order, the uninstall process displays message prompts stating that System Architect XT will not work after removing System Architect, because they share common components. Furthermore, the reverse sequence leaves some files in the installation path.
See also
Installing SA and SA XT on same machine