emma: 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/emma - from package: emboss
/usr/bin/emma - from package: emma

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