The first time you use the “Export as MP3” command Audacity will ask for the location of “lame_enc.dll”. You can download the Microsoft Windows version of the file HERE.

Once the file has been downloaded, go back to Audacity ( the free open source editor for sound and music ) and use the export as MP3 command, then select the file location you have downloaded “lame_enc.dll” to and then click “Open” and “OK”.

You can find more information about Audacity on the FAQ section of the site.