gvfs-open: 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 CentOS possible default full paths are:

/usr/bin/gvfs-open - from package: gvfs

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

On Debian possible default full paths are:

/usr/bin/gvfs-open - from package: gvfs-bin

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