Both local and network client installations include a mini Explorer installation as a component. This installation includes the file Shdocvw.dll. This file needs to be on the client machine even for a thin client installation, and should be located in a System folder, for example, System32. The file Shdocvw.dll is a self-registering file that you need to register.
An additional installed file, Apitools.exe, can reside anywhere and does not require registration. In a network client installation, this file resides on the application server.