nces: 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/nces - from package: nco

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

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