maq_plot.pl: 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/maq_plot.pl - from package: maq

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

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