gexamp: 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/gexamp - from package: pvm-examples

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

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