wmforkplop: 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/wmforkplop - from package: wmforkplop

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

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