applygnupgdefaults: 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 CentOS possible default full paths are:

/usr/sbin/applygnupgdefaults - from package: gnupg2

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/applygnupgdefaults - from package: gnupg2

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