When I open an existing erwin model in erwin Data Modeler R9.x, no changes to the model are made, and do a File | Close, the Save Model dialog opens with a selection to save or not save the model.  Why is the Save Model dialog appearing?  This did not occur with erwin Data Modeler r8.x  models.

Solution:

The difference between erwin Data Modeler r8.x and r9.x is that in r9.x, DSM/NSM is included in the model. In r9.x, when we open an erwin model with DSM/NSM attached, erwin needs to refresh the objects to update in current diagram. In r8.x, one needed to reload the NSM, DSM manually after the model was opened otherwise the column names, datatypes did not display correctly. If you reloaded NSM, DSM in r8.x, the Save model also prompted for Save. So, in r9.x, the NSM, DSM is applied after the model is loaded whereas in r8.x, the applied NSM, DSM was stored in the model so nothing was refreshed.  Even in r9, if there is no DSM, NSM in the model, it will not prompt for Save.