file: 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/file - from package: file

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

On Debian possible default full paths are:

/usr/bin/file - from package: file

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

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