showpr: 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/share/doc/mh-book/examples/mh/bin/showpr - from package: mh-book

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

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