diff --git a/src/Mod/Fem/App/PropertyPostDataObject.cpp b/src/Mod/Fem/App/PropertyPostDataObject.cpp
index 89e6130f68..6634ccc2d0 100644
--- a/src/Mod/Fem/App/PropertyPostDataObject.cpp
+++ b/src/Mod/Fem/App/PropertyPostDataObject.cpp
@@ -220,7 +220,7 @@ void PropertyPostDataObject::Paste(const App::Property &from)
 
 unsigned int PropertyPostDataObject::getMemSize(void) const
 {
-    return m_dataObject->GetActualMemorySize();
+    return m_dataObject ? m_dataObject->GetActualMemorySize() : 0;
 }
 
 void PropertyPostDataObject::getPaths(std::vector<App::ObjectIdentifier> & /*paths*/) const