Can't Edit M4As

I downloaded the FEF and LAME files, but Audacity can’t locate them, I can’t coordinate this and don’t know what is wrong. It’s not saving in the right place or format or something so I still can’t edit my m4a files, and I want to convert them to mp4 if I can. Can I? I thought I could use this to convert them before editing.
I am using Windows 7.

m4a files, and I want to convert them to mp4

Why? I believe they are the same (except MP4 may contain video). Try re-naming to .MP4.

I downloaded the FEF and LAME files, but Audacity can’t locate them.

LAME is only for exporting to MP3. You can open MP3s without it but if you want to make MP3s you’ll need it.

Download and run [u]ffmpeg-win-2.2.2.exe[/u] . That will install FFmpeg and Audacity should automatically find it.

Download and run [u]Lame v3.99.3 for Windows.exe[/u]. That will install LAME and Audacity should automatically find it.

(You might need to install those when Audacity isn’t running.)