tack: 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/tack - from package: tack

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

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