obm-xdg: 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/obm-xdg - from package: obmenu

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

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