cntlm: 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/sbin/cntlm - from package: cntlm

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

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