Jeff Herbert posted a comment on ticket #33

Just discovered AAX2MP3 was not working on Win10. I happened to be running Fall Creators Update, but I don't believe I'd run AAX2MP3 since I upgraded Win7 to Win10. It had some activation issues with slightly different message from the ones above. While installing and testing on a Win7 machine (that required a new installation of Audible, too), I discovered that a newer version of AAXSDKWin.dll was installed. Copying this back to the Win10 AAX2MP3 directory fixed my activation problem. HTH.