ntfs-3g.usermap: 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:

/bin/ntfs-3g.usermap - from package: ntfs-3g

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

On Debian possible default full paths are:

/bin/ntfs-3g.usermap - from package: ntfs-3g

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

Error in other languages:
ntfs-3g.usermap: bevel nie gevind nie
ntfs-3g.usermap: comandă negăsită
ntfs-3g.usermap: comando não encontrado
ntfs-3g.usermap: commande introuvable
ntfs-3g.usermap: command not found
ntfs-3g.usermap: käsku ei ole
ntfs-3g.usermap: không tìm thấy lệnh
ntfs-3g.usermap: komanda nerasta
ntfs-3g.usermap: Kommando nicht gefunden.
ntfs-3g.usermap: kommandot finns inte
ntfs-3g.usermap: komut yok
ntfs-3g.usermap: nie znaleziono polecenia
ntfs-3g.usermap: níor aimsíodh an t-ordú
ntfs-3g.usermap: no se encontró la orden
ntfs-3g.usermap: no s'ha trobat l'ordre
ntfs-3g.usermap: opdracht niet gevonden
ntfs-3g.usermap: parancs nem található
ntfs-3g.usermap: perintah tidak ditemukan
ntfs-3g.usermap: príkaz nenájdený
ntfs-3g.usermap: příkaz nenalezen
ntfs-3g.usermap: команда не найдена
ntfs-3g.usermap: командата не е открита
ntfs-3g.usermap: 命令找不到
ntfs-3g.usermap: コマンドが見つかりません