Setup Arduino in Simulink port connection issue

I am trying to run the simple led tutorial but when I choose the correct port(COM4) it will not connect and I get a timeout error. The default port is DEMO and I don't get an error message and the program runs but it doesn't actually do anything in terms of communicating with the board. Any suggestions?

[Prashant]

A basic checklist below :

1. Check if your arduino is actually on COM4 from Windows Device manager.
2. Ensure you've selected correct arduino board in simulink hardware configuration
3. Program your board using Arduino IDE to make sure your board is in working condition.
4. Ensure your Arduino board is supported by the version of Simulink you're using.
5. I don't believe there's any "Demo" port in simulink. Did you mean "Auto" ? If so, refer to step 1 above.
6. Ensure the blocks used in your model are supported by Arduino board.
7. Verify pin number for your Arduino board. THis always gets me as i work with several version of arduino boards.