If the item doesn't exist anymore, remove it from storage to avoid crashes

src/main/java/refinedstorage/tile/TileController.java

@@ -186,6 +186,10 @@ public class TileController extends TileBase implements IEnergyReceiver, INetwor
 
             ItemGroup group = itemGroups.get(i);
 
+            // If the item doesn't exist anymore, remove it from storage to avoid crashes
+            if (group.getType() == null) {
+                markedIndexes.add(i);
+            } else {
                 for (int j = i + 1; j < itemGroups.size(); ++j) {
                     if (markedIndexes.contains(j)) {
                         continue;
@@ -200,6 +204,7 @@ public class TileController extends TileBase implements IEnergyReceiver, INetwor
                     }
                 }
             }
+        }
 
         List<ItemGroup> markedItems = new ArrayList<ItemGroup>();