ktelnetservice: 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 CentOS possible default full paths are:

/usr/bin/ktelnetservice - from package: kdelibs3

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/ktelnetservice - from package: kdelibs-bin

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

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