flasm: 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/flasm - from package: flasm

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