If the app you are trying to run came with its own "redistributable" or "installer" package, try running that setup file again. It may have failed to extract the DLL correctly during the first installation. ⚠️ A Note on Safety Never download individual DLL files
: The Windows PATH environment variable does not point to the folder containing the DLL. Recommended Solutions 1. Install/Reinstall MATLAB Runtime R2020b mclmcrrt9-9.dll