Default Crashed tablet reflash

I have Arnova 10d G3 tablet. long time ago it crashed(stuck on bootup screen), so I reflashed it with Android 4.1(default I think was 4.0). After some time it got buggy and I reflashed it again.
Now it again is stuck on Bootup and I can't even reflash it or access recovery mode.
I am reflashing it after instruction on some site (put script file and a folder in SD card and turn on tablet). But now nothing happens when I try to reflash it.