hardinfo: 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/hardinfo - from package: hardinfo

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

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