mshowfat: 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:

/usr/bin/mshowfat - from package: mtools

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

On Debian possible default full paths are:

/usr/bin/mshowfat - from package: mtools

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

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