E- (SPMHAC-31): The element from which you are connecting is not on the subclass. Use "Add Via".

 I am wondering if below error is a bug from Allegro 16.6 or there is something wrong with my settings.

E- (SPMHAC-31): The element from which you are connecting is not on the subclass.  Use "Add Via".

That happens randomly and sometimes dissapeares with itterations?! ;-(

Is there anybody who knows the issue?

Thanks,

Hossein