fprintd: 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/sbin/fprintd - from package: fprintd

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

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