kpasswd: 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/kpasswd - from package: heimdal-workstation
/usr/bin/kpasswd - from package: krb5-workstation

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

On Debian possible default full paths are:

/usr/bin/kpasswd - from package: krb5-user
/usr/bin/kpasswd - from package: openafs-kpasswd

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

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