kgrantpty: 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/kgrantpty - from package: kdelibs3

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

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