ntfslabel: 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:

/sbin/ntfslabel - from package: ntfsprogs
/usr/sbin/ntfslabel - from package: ntfsprogs

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

On Debian possible default full paths are:

/sbin/ntfslabel - from package: ntfs-3g

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

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