expect_tknewsbiff: 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/expect_tknewsbiff - from package: expect

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

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