yapet: 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/yapet - from package: yapet

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

On Debian possible default full paths are:

/usr/bin/yapet - from package: yapet

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

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