marscan: 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/marscan - from package: emboss

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

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