ANTS: 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/ANTS - from package: ants

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

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