folks-inspect: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/folks-inspect - from package: folks-tools

You may install the required package with command apt-get install {package}

Error in other languages:
folks-inspect: bevel nie gevind nie
folks-inspect: comandă negăsită
folks-inspect: comando não encontrado
folks-inspect: commande introuvable
folks-inspect: command not found
folks-inspect: käsku ei ole
folks-inspect: không tìm thấy lệnh
folks-inspect: komanda nerasta
folks-inspect: Kommando nicht gefunden.
folks-inspect: kommandot finns inte
folks-inspect: komut yok
folks-inspect: nie znaleziono polecenia
folks-inspect: níor aimsíodh an t-ordú
folks-inspect: no se encontró la orden
folks-inspect: no s'ha trobat l'ordre
folks-inspect: opdracht niet gevonden
folks-inspect: parancs nem található
folks-inspect: perintah tidak ditemukan
folks-inspect: príkaz nenájdený
folks-inspect: příkaz nenalezen
folks-inspect: команда не найдена
folks-inspect: командата не е открита
folks-inspect: 命令找不到
folks-inspect: コマンドが見つかりません