dot-forward: 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/dot-forward - from package: dot-forward
/var/lib/qmail/bin/dot-forward - from package: dot-forward

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

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