spectool_curses: 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/spectool_curses - from package: spectools

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