pike7.8: 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/pike7.8 - from package: pike7.8-core

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

Error in other languages:
pike7.8: bevel nie gevind nie
pike7.8: comandă negăsită
pike7.8: comando não encontrado
pike7.8: commande introuvable
pike7.8: command not found
pike7.8: käsku ei ole
pike7.8: không tìm thấy lệnh
pike7.8: komanda nerasta
pike7.8: Kommando nicht gefunden.
pike7.8: kommandot finns inte
pike7.8: komut yok
pike7.8: nie znaleziono polecenia
pike7.8: níor aimsíodh an t-ordú
pike7.8: no se encontró la orden
pike7.8: no s'ha trobat l'ordre
pike7.8: opdracht niet gevonden
pike7.8: parancs nem található
pike7.8: perintah tidak ditemukan
pike7.8: príkaz nenájdený
pike7.8: příkaz nenalezen
pike7.8: команда не найдена
pike7.8: командата не е открита
pike7.8: 命令找不到
pike7.8: コマンドが見つかりません