will_oops: 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/will_oops - from package: will-crash

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

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