mpif77.lam: 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/mpif77.lam - from package: lam4-dev

You may install the required package with command apt-get install {package}
Error in other languages:
mpif77.lam: bevel nie gevind nie
mpif77.lam: comandă negăsită
mpif77.lam: comando não encontrado
mpif77.lam: commande introuvable
mpif77.lam: command not found
mpif77.lam: käsku ei ole
mpif77.lam: không tìm thấy lệnh
mpif77.lam: komanda nerasta
mpif77.lam: Kommando nicht gefunden.
mpif77.lam: kommandot finns inte
mpif77.lam: komut yok
mpif77.lam: nie znaleziono polecenia
mpif77.lam: níor aimsíodh an t-ordú
mpif77.lam: no se encontró la orden
mpif77.lam: no s'ha trobat l'ordre
mpif77.lam: opdracht niet gevonden
mpif77.lam: parancs nem található
mpif77.lam: perintah tidak ditemukan
mpif77.lam: príkaz nenájdený
mpif77.lam: příkaz nenalezen
mpif77.lam: команда не найдена
mpif77.lam: командата не е открита
mpif77.lam: 命令找不到
mpif77.lam: コマンドが見つかりません