mifare-ultralight-info: 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 Debian possible default full paths are:

/usr/bin/mifare-ultralight-info - from package: libfreefare-bin

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

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