radiotray: 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/radiotray - from package: radiotray

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

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