encapsulate: 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 Debian possible default full paths are:

/usr/bin/encapsulate - from package: netpipes

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

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