sysv-rc-conf: 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/sysv-rc-conf - from package: sysv-rc-conf

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

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