mcomix: 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/mcomix - from package: mcomix

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

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