hesinfo: 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 CentOS possible default full paths are:

/usr/bin/hesinfo - from package: hesinfo

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/hesinfo - from package: hesiod

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

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