The issue arises because the mask initialization commands in your adder block are attempting to modify parameters of a block that is part of a library link. Simulink restricts modifications to library-linked blocks to ensure consistency across models using the library.
To resolve this issue, you can allow the library blocks to modify their contents by adjusting the mask settings:
- Open your library file in Simulink.
- Navigate to the adder block and open the Mask Editor.
- Go to the "Code" tab.
- In different releases of MATLAB, this final step may differ.
- In MATLAB R2023a or later, in the “Mask Editor”, navigate to the “Code” tab and click the "Allow mask initialization code to modify the subsystem's content" checkbox.
- From MATLAB R2022a to MATLAB R2022b, in the “Mask Editor”, navigate to the “Code” tab and click the “Allow library blocks to modify its contents” checkbox.
- In earlier releases of MATLAB, in the "Mask Editor", navigate to the "Initialization" pane and click "Allow library blocks to modify its contents" checkbox.
