eggdrop-1.6.21: 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/eggdrop-1.6.21 - from package: eggdrop

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

Error in other languages:
eggdrop-1.6.21: bevel nie gevind nie
eggdrop-1.6.21: comandă negăsită
eggdrop-1.6.21: comando não encontrado
eggdrop-1.6.21: commande introuvable
eggdrop-1.6.21: command not found
eggdrop-1.6.21: käsku ei ole
eggdrop-1.6.21: không tìm thấy lệnh
eggdrop-1.6.21: komanda nerasta
eggdrop-1.6.21: Kommando nicht gefunden.
eggdrop-1.6.21: kommandot finns inte
eggdrop-1.6.21: komut yok
eggdrop-1.6.21: nie znaleziono polecenia
eggdrop-1.6.21: níor aimsíodh an t-ordú
eggdrop-1.6.21: no se encontró la orden
eggdrop-1.6.21: no s'ha trobat l'ordre
eggdrop-1.6.21: opdracht niet gevonden
eggdrop-1.6.21: parancs nem található
eggdrop-1.6.21: perintah tidak ditemukan
eggdrop-1.6.21: príkaz nenájdený
eggdrop-1.6.21: příkaz nenalezen
eggdrop-1.6.21: команда не найдена
eggdrop-1.6.21: командата не е открита
eggdrop-1.6.21: 命令找不到
eggdrop-1.6.21: コマンドが見つかりません