For unknown reasons the file 'workspace/<your_project>/.rs.xml' can become corrupted. This will cause the XML parser to thrown an exception. This type of issue maybe due to disk IO, disk capacity, or something else while updating the .rs.xml file.
When opening the Tivoli Directory Integrator - Config Editor, the following message will be shown within the panels of the Tivoli Directory Integrator Perspective.
'Could not open the editor: org.xml.sax.SAXParseException: XML document structures must start and end within the same entity.'
Resolving the problem
1. Based on the Assemblyline Tab which is opened in the Config Editor, find the 'workspace/project' directory which the Assemblyline is associated with.
2. Once the project directory is found, remove the 'workspace/project/.rs.xml' file found within the directory.