libplayer-testvdr: 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/libplayer-testvdr - from package: libplayer-bin

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

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