update-nfonts: 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/update-nfonts - from package: mknfonts.tool

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

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