scantailor: 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/scantailor - from package: scantailor

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

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