diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CContentOutlinePage.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CContentOutlinePage.java
index 90aebdc0039..dd1977eef18 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CContentOutlinePage.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CContentOutlinePage.java
@@ -224,8 +224,11 @@ public class CContentOutlinePage extends Page implements IContentOutlinePage, IS
 	}
 
 	protected CContentOutlinerProvider createContentProvider(TreeViewer viewer) {
-		IWorkbenchPartSite site= getSite().getPage().getActiveEditor().getSite();
-		return new CContentOutlinerProvider(viewer, site);
+		IWorkbenchPart part= getSite().getPage().getActivePart();
+		if (part == null) {
+			return new CContentOutlinerProvider(viewer);
+		}
+		return new CContentOutlinerProvider(viewer, part.getSite());
 	}
 
 	protected ProblemTreeViewer createTreeViewer(Composite parent) {