fsck.msdos: 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/fsck.msdos - from package: dosfstools

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

On Debian possible default full paths are:

/sbin/fsck.msdos - from package: dosfstools

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

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