pfsinmulti: command not found

Have You tried accessing the binary with the full path?

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/pfsinmulti - from package: pfstools

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