mknfonts: command not found

Have You tried accessing the binary with the full path?

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/mknfonts - from package: mknfonts.tool

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