pdetach: 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/pdetach - from package: ucommon-bin

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

On Debian possible default full paths are:

/usr/bin/pdetach - from package: ucommon-utils

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

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