dbck: 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/sbin/dbck - from package: lyskom-server

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

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