Why do I get the error "Object parameter contains an invalid handle" when running a model which contains a Stateflow chart in Simulink 7.3 (R2009a)?

I had a demo Stateflow license that just expired. The model I was working on contains a simple chart. Upon opening the model, 30+ error dialogs popped up warning me not able to save or simulate without stateflow license. I deleted the stateflow block and tried to update the diagram, another 30+ error dialog popped up though I don't have any stateflow chart anywhere in the model any more. I cannot even save the model.

I receive the following error:

 Object parameter contains an invalid handle

Answer 1

[MathWorks Support Team]

This error is due to the fact that you do not have a Stateflow license available to be checked out at this time. Each Stateflow chart is linked to the Stateflow library and thus requires a license even when only running a model which contains a Stateflow chart.

Check with your System Administrator if you are having trouble checking out a license for Stateflow.

As a workaround, you may follow the following steps to restore your model to a workable state.

1) Delete ALL instances of Stateflow charts and variables from your model. This must include all possible references that may invoke the check_license for Stateflow.

2) From the Model Editor (main window) select Edit->Select All, then Edit -> Copy

3) Paste the copied blocks into a new model and save under a new name.

4) Close all models and close MATLAB and Simulink.

5) Relaunch Simulink and open the newly saved model without the Stateflow blocks.