I've just been trying to set up FFmpeg here (well, got the guys at ServInt to do it infact), but running FFmpeg gave me this error:
ffmpeg: error while loading shared libraries: libavformat.so.51: cannot open shared object file: No such file or directory
My linux knowledge is coming up short here, so I dug around for a solution:
Edit /etc/ld.so.conf and add the line
/usr/local/lib
then save and exit.
Now run this command:
ldconfig -v
I'm just documenting this here to help others and help me when I have to do this again on the live server after Xmas.