Hi,
In order for TestComplete to stop the test run when an exception occurs, follow the steps below:
1. Add your test to the Test Items page of the project editor.
2. In the Stop on Exception column, select Test Item.
3. Disable the project's Error dialog option.
4. Run the project. TestComplete will run the test. When an exception occurs, TestComplete will not display an error dialog and stop the test run.
You can also create an OnStopTest event handler to perform the needed actions after the test run is stopped. TestComplete will perform these actions just once the exception occurs.