fvwm-crystal.infoline: 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/fvwm-crystal.infoline - from package: fvwm-crystal

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

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