multicat_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/multicat_validate - from package: multicat

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

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