Cannot edit a feature layer when I start a session editing - gis

Question

I am developing a standalone app based on ArcGIS Engine, and when I starting a session editing with the code block below:
//Declare the Engine editor at the class level.
private IEngineEditor m_engineEditor = new EngineEditorClass();
private void StartEditing(IMapControl2 m_mapControl)
{
IMap map = m_mapControl.Map;
//If an edit session has already been started, exit.
if (m_engineEditor.EditState != esriEngineEditState.esriEngineStateNotEditing)
return ;
//Start editing the workspace of the first feature layer found.
for (int layerCounter = 0; layerCounter <= map.LayerCount - 1; layerCounter++)
{
ILayer currentLayer = map.get_Layer(layerCounter);
if (currentLayer is IFeatureLayer)
{
IFeatureLayer featureLayer = currentLayer as IFeatureLayer;
IDataset dataset = featureLayer.FeatureClass as IDataset;
IWorkspace workspace = dataset.Workspace;
m_engineEditor.StartEditing(workspace, map);
((IEngineEditLayers)m_engineEditor).SetTargetLayer(featureLayer);
break;
}
}
}
An exception occurred with error code: HRESULT: 0x80004005 (E_FAIL)). Please help me

Answer 1

After asking Google and reading ArcGIS Engine documents. I found my SDE GeoDatabase does not allow editing data, because I turn off version manager of ArcGIS GeoDatabase. Turn on it and add some code to check feature layer is editable.
IEngineEditLayers m_engineLayersEditor = m_engineEditor as IEngineEditLayers;
if (!m_engineLayersEditor.IsEditable(featureLayer))
{
MessageBox.Show("Can not start editing. Because feature layer is not allow editing", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}