Why does running afconvert result in error -43 I am trying to use afconvert to convert a .mp3 to .m4r. I am entering the following:

afconvert -f m4af -d aac -o input.mp3 tone.m4r


However, this gives me an error:

Error: Couldn't open input file (-43)


I am in the directory of the input file. Could someone please shed some light on what I am doing wrong?
Drop the -o flag, I think. You are specifying input.mp3 as an output file, and then tone.m4r becomes the input file. See the output of afconvert -h.