rss-glx_install: 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/rss-glx_install - from package: rss-glx

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

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