bunzip2: 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/bunzip2 - from package: bzip2

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

On Debian possible default full paths are:

/bin/bunzip2 - from package: bzip2

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

Error in other languages:
bunzip2: bevel nie gevind nie
bunzip2: comandă negăsită
bunzip2: comando não encontrado
bunzip2: commande introuvable
bunzip2: command not found
bunzip2: käsku ei ole
bunzip2: không tìm thấy lệnh
bunzip2: komanda nerasta
bunzip2: Kommando nicht gefunden.
bunzip2: kommandot finns inte
bunzip2: komut yok
bunzip2: nie znaleziono polecenia
bunzip2: níor aimsíodh an t-ordú
bunzip2: no se encontró la orden
bunzip2: no s'ha trobat l'ordre
bunzip2: opdracht niet gevonden
bunzip2: parancs nem található
bunzip2: perintah tidak ditemukan
bunzip2: príkaz nenájdený
bunzip2: příkaz nenalezen
bunzip2: команда не найдена
bunzip2: командата не е открита
bunzip2: 命令找不到
bunzip2: コマンドが見つかりません