tv_check: 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/tv_check - from package: xmltv-gui

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