diff --git a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CProject.java b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CProject.java
index bfedb1f9e71..4f69e4c24b7 100644
--- a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CProject.java
+++ b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CProject.java
@@ -776,12 +776,13 @@ public class CProject extends Openable implements ICProject {
 			String tuName = memento.nextToken();
 			final IPath path= Path.fromPortableString(tuName);
 			CElement tu= null;
-			try {
-				tu= (CElement) findElement(path);
-			} catch (CModelException exc) {
-				CCorePlugin.log(exc);
-			}
-			if (tu == null) {
+			if (!path.isAbsolute()) {
+				try {
+					tu= (CElement) findElement(path);
+				} catch (CModelException exc) {
+					CCorePlugin.log(exc);
+				}
+			} else {
 				tu= (CElement) CoreModel.getDefault().createTranslationUnitFrom(this, path);
 			}
 			if (tu != null) {
diff --git a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/TranslationUnit.java b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/TranslationUnit.java
index 6f04ab921ed..b36022e131f 100644
--- a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/TranslationUnit.java
+++ b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/TranslationUnit.java
@@ -1074,7 +1074,10 @@ public class TranslationUnit extends Openable implements ITranslationUnit {
 		if (getResource() == null) {
 			((CElement)getCProject()).getHandleMemento(buff);
 			buff.append(getHandleMementoDelimiter());
-			escapeMementoName(buff, getPath().toPortableString());
+			final IPath location= getLocation();
+			if (location != null) {
+				escapeMementoName(buff, location.toPortableString());
+			}
 		} else {
 			super.getHandleMemento(buff);
 		}
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/util/EditorUtility.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/util/EditorUtility.java
index ba7fbd393bb..ece03a2333b 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/util/EditorUtility.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/util/EditorUtility.java
@@ -638,7 +638,15 @@ public class EditorUtility {
 					cProject= null;
 			}
 		} else if (input instanceof ITranslationUnitEditorInput) {
-			cProject= ((ITranslationUnitEditorInput)input).getTranslationUnit().getCProject();
+			final ITranslationUnit tu= ((ITranslationUnitEditorInput)input).getTranslationUnit();
+			if (tu != null) {
+				cProject= tu.getCProject();
+			} else if (input instanceof ExternalEditorInput) {
+				IResource resource= ((ExternalEditorInput) input).getMarkerResource();
+				if (resource instanceof IProject) {
+					cProject= CoreModel.getDefault().create((IProject) resource);
+				}
+			}
 		}
 		return cProject;
 	}