Why do I receive the following error when trying to connect to Arduino Hardware with the MATLAB support package?

ERROR: Failed to open serial port COM6 to communicate with board Uno. Make
sure there is no other MATLAB arduino object for this board. For
troubleshooting, see Arduino Hardware Troubleshooting.
Correspondingly using the Simulink Support Package for Arduino, why do I receive the following error when building a model for the Arduino?

ERROR: Open fail: Port: COM* is not available. No ports are available.
Use INSTRFIND to determine if other instrument objects are connected to the requested device.Why do I receive the following error when trying to connect to Arduino Hardware with the MATLAB support package?

ERROR: Failed to open serial port COM6 to communicate with board Uno. Make
sure there is no other MATLAB arduino object for this board. For
troubleshooting, see Arduino Hardware Troubleshooting.
Correspondingly using the Simulink Support Package for Arduino, why do I receive the following error when building a model for the Arduino?

ERROR: Open fail: Port: COM* is not available. No ports are available.
Use INSTRFIND to determine if other instrument objects are connected to the requested device. Why do I receive the following error when trying to connect to Arduino Hardware with the MATLAB support package?

ERROR: Failed to open serial port COM6 to communicate with board Uno. Make
sure there is no other MATLAB arduino object for this board. For
troubleshooting, see Arduino Hardware Troubleshooting.
Correspondingly using the Simulink Support Package for Arduino, why do I receive the following error when building a model for the Arduino?

ERROR: Open fail: Port: COM* is not available. No ports are available.
Use INSTRFIND to determine if other instrument objects are connected to the requested device.  MATLAB Answers — New Questions

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