promer: 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/promer - from package: mummer

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

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