json-glib-validate: 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/json-glib-validate - from package: json-glib-tools

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

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