ktutil: 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/lib/heimdal/bin/ktutil - from package: heimdal-workstation
/usr/bin/ktutil - from package: krb5-workstation

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

On Debian possible default full paths are:

/usr/bin/ktutil - from package: krb5-user

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

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