tinydyndns-conf: 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/tinydyndns-conf - from package: tinydyndns

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

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