wmanager-loop: command not found

Have You tried accessing the binary with the full path?

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/wmanager-loop - from package: wmanager

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