stpm-keygen: 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/stpm-keygen - from package: simple-tpm-pk11

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

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