amavisd-snmp-subagent-zmq: 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/sbin/amavisd-snmp-subagent-zmq - from package: amavisd-new

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