diff --git a/pcbnew/class_board.cpp b/pcbnew/class_board.cpp
index e04ca8143f..c0ac1f8119 100644
--- a/pcbnew/class_board.cpp
+++ b/pcbnew/class_board.cpp
@@ -3020,3 +3020,38 @@ void BOARD::ClearAllNetCodes()
     for( auto track : Tracks() )
         track->SetNetCode( 0 );
 }
+
+const std::vector<BOARD_CONNECTED_ITEM*> BOARD::AllConnectedItems()
+{
+    std::vector<BOARD_CONNECTED_ITEM*> items;
+
+    for( auto track : Tracks() )
+    {
+        items.push_back( track );
+    }
+
+    for( auto mod : Modules() )
+    {
+        for( auto pad : mod->Pads() )
+        {
+            items.push_back( pad );
+        }
+    }
+
+    for( int i = 0; i<GetAreaCount(); i++ )
+    {
+        auto zone = GetArea( i );
+        items.push_back( zone );
+    }
+
+    return items;
+}
+
+void BOARD::SanitizeNetcodes()
+{
+    for ( auto item : AllConnectedItems() )
+    {
+        if( FindNet( item->GetNetCode() ) == nullptr )
+            item->SetNetCode( NETINFO_LIST::ORPHANED );
+    }
+}
diff --git a/pcbnew/class_board.h b/pcbnew/class_board.h
index a8a585157c..7074abf497 100644
--- a/pcbnew/class_board.h
+++ b/pcbnew/class_board.h
@@ -254,7 +254,7 @@ public:
     DLIST_ITERATOR_WRAPPER<MODULE> Modules() { return DLIST_ITERATOR_WRAPPER<MODULE>(m_Modules); }
     DLIST_ITERATOR_WRAPPER<BOARD_ITEM> Drawings() { return DLIST_ITERATOR_WRAPPER<BOARD_ITEM>(m_Drawings); }
     ZONE_CONTAINERS& Zones() { return m_ZoneDescriptorList; }
-
+    const std::vector<BOARD_CONNECTED_ITEM*> AllConnectedItems();
 
     // will be deprecated as soon as append board functionality is fixed
     DLIST<BOARD_ITEM>&          DrawingsList() { return m_Drawings; }
@@ -1358,6 +1358,8 @@ public:
      * Resets all items' netcodes to 0 (no net).
      */
     void ClearAllNetCodes();
+
+    void SanitizeNetcodes();
 };
 
 #endif      // CLASS_BOARD_H_
diff --git a/pcbnew/undo_redo.cpp b/pcbnew/undo_redo.cpp
index 46f63f88dc..06930609cb 100644
--- a/pcbnew/undo_redo.cpp
+++ b/pcbnew/undo_redo.cpp
@@ -581,13 +581,15 @@ void PCB_BASE_EDIT_FRAME::PutDataInPreviousState( PICKED_ITEMS_LIST* aList, bool
 
     if( not_found )
         wxMessageBox( wxT( "Incomplete undo/redo operation: some items not found" ) );
-
+    
     // Rebuild pointers and connectivity that can be changed.
     // connectivity can be rebuilt only in the board editor frame
     if( IsType( FRAME_PCB ) && ( reBuild_ratsnest || deep_reBuild_ratsnest ) )
     {
         Compile_Ratsnest( NULL, false );
     }
+
+    GetBoard()->SanitizeNetcodes();
 }