When trying to uninstall the ProjectWise DCS (Dynamic Composition Server) the following error occurs:
(Object reference not set to an instance of an object.)
And then the following error:
After that the uninstallation rolls back.
The issue occurs because the Interplot Organizer was removed before uninstalling the DCS. The DCS uninstallation process tries to locate the Interplot Organizer registry keys and it fails.
To resolve this issue it is required to install back the Interplot Organizer. After that the DCS uninstall will finish successfully.
Encountered this recently and the only way I could resolve was to use the following Microsoft Tool; support2.microsoft.com/default.aspx;en-us;290301