ntfsck: 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/ntfsck - from package: ntfsprogs
/usr/bin/ntfsck - from package: ntfsprogs

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

On Debian possible default full paths are:

/usr/bin/ntfsck - from package: ntfs-3g-dev

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

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