tvtime-configure: 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/tvtime-configure - from package: tvtime

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

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