photoprint: 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

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/photoprint - from package: photoprint

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