burnK7: 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/burnK7 - from package: cpuburn

You may install the required package with command apt-get install {package}
Error in other languages:
burnK7: bevel nie gevind nie
burnK7: comandă negăsită
burnK7: comando não encontrado
burnK7: commande introuvable
burnK7: command not found
burnK7: käsku ei ole
burnK7: không tìm thấy lệnh
burnK7: komanda nerasta
burnK7: Kommando nicht gefunden.
burnK7: kommandot finns inte
burnK7: komut yok
burnK7: nie znaleziono polecenia
burnK7: níor aimsíodh an t-ordú
burnK7: no se encontró la orden
burnK7: no s'ha trobat l'ordre
burnK7: opdracht niet gevonden
burnK7: parancs nem található
burnK7: perintah tidak ditemukan
burnK7: príkaz nenájdený
burnK7: příkaz nenalezen
burnK7: команда не найдена
burnK7: командата не е открита
burnK7: 命令找不到
burnK7: コマンドが見つかりません