matchbox-window-manager: 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 CentOS possible default full paths are:

/usr/bin/matchbox-window-manager - from package: matchbox-window-manager

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/matchbox-window-manager - from package: matchbox-window-manager

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

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