The UpdateState method updates the status of importing the incremental hierarchy changes.
HRESULT UpdateState(
LPSTREAM lpStream
);
See Return Values.
In addition, UpdateState can return one of the following values:
The agent must use a different IStream interface if it is going to shut down and resume later, or if it is checkpointing the progress of the incremental change synchronization.
IExchangeExportChanges::Config, IExchangeImportContentsChanges::UpdateState, IExchangeImportHierarchyChanges