in.fakepop: 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/sbin/in.fakepop - from package: fakepop

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

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