Could not open MP3 encoding library!

Audacity 2.1.0
MacOS Mojave 10.14.3.

I’ve installed the recommended MP3 encoding library.
However, when I try to export an MP3, I get the error message “Could not open MP3 encoding library!”.

I’ve tried to set the location in preferences to /Library/Application Support/audacity/libs/libmp3lame64bit.dylib
Although there is no error message this doesn’t work.

Can anyone help?

For Audacity 2.1.0 you need the old (32-bit) LAME dylib. Either upgrade to Audacity 2.3.1, or install the 32-bit library.
– Bill