Are you finding d3d9.dll just press download button to get your d3d9.dll file.
If some software in your windows OS wants d3d9.dll your operating system will ask for DLL file. When that DLL file is not available you will get this error.
If you have moved your file or changed the name of dll file you will get this error.
You will mostly see there errors when you dll file is missing:
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