pure-statsdecode: 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/pure-statsdecode - from package: pure-ftpd

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

On Debian possible default full paths are:

/usr/bin/pure-statsdecode - from package: pure-ftpd-ldap
/usr/bin/pure-statsdecode - from package: pure-ftpd-mysql
/usr/bin/pure-statsdecode - from package: pure-ftpd-postgresql
/usr/bin/pure-statsdecode - from package: pure-ftpd

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

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