FFmpeg not found.

Just got the ffmpeg not found message, only just happened between exporting multiples, so I promptly downloaded the necessary file for the library, BUT, Audacity cant see it or pick it up on my laptop. I have downloaded it three times now all to no avail, even reinstalled Audacity - I am not a total ‘newbie’ but I cant see why this is happening. Help and advice please.

Ensure that you precisely follow the instructions here: http://manual.audacityteam.org/o/man/faq_installation_and_plug_ins.html#ffdown

Followed the procedure precisely and still ‘no go’ dont know where now, download as MP3 and convert with alternative software I suppose.??

Which exact version of Audacity are you using? (look in “Help > About Audacity” for the version number).

What exactly happens (step-by-step) when you go through the steps to Locate the FFmpeg library manually ?

No, best not to do that as that will then be doing two “lossy compression” steps which will adversely affect the sound quality.
If all else fails you could export as WAV format and then convert the WAV file with a third party encoder.