prewikka-httpd: 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/prewikka-httpd - from package: prewikka

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

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