kradio4-convert-presets: 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
/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/kradio4-convert-presets - from package: kradio4

You may install the required package with command apt-get install {package}
Error in other languages:
kradio4-convert-presets: bevel nie gevind nie
kradio4-convert-presets: comandă negăsită
kradio4-convert-presets: comando não encontrado
kradio4-convert-presets: commande introuvable
kradio4-convert-presets: command not found
kradio4-convert-presets: käsku ei ole
kradio4-convert-presets: không tìm thấy lệnh
kradio4-convert-presets: komanda nerasta
kradio4-convert-presets: Kommando nicht gefunden.
kradio4-convert-presets: kommandot finns inte
kradio4-convert-presets: komut yok
kradio4-convert-presets: nie znaleziono polecenia
kradio4-convert-presets: níor aimsíodh an t-ordú
kradio4-convert-presets: no se encontró la orden
kradio4-convert-presets: no s'ha trobat l'ordre
kradio4-convert-presets: opdracht niet gevonden
kradio4-convert-presets: parancs nem található
kradio4-convert-presets: perintah tidak ditemukan
kradio4-convert-presets: príkaz nenájdený
kradio4-convert-presets: příkaz nenalezen
kradio4-convert-presets: команда не найдена
kradio4-convert-presets: командата не е открита
kradio4-convert-presets: 命令找不到
kradio4-convert-presets: コマンドが見つかりません