scanmem: 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/scanmem - from package: scanmem

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

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