did you try this tip ?
you need download the last official firmware
The downloaded firmware appropriate for your device (named firmware_archos_it4.aos)
Entering in recovery mode
The tablet must be off (push the power button for 10 secs).
Plug the USB cable into the PC (do not plug into the tablet yet).
Press & hold Volume +
Now plug the USB lead into the tablet
A white boot menu should appear, you can release Volume +
Use the volume buttons to navigate and validate with ON/OFF
If you failed to access to the recovery menu, please start again from the beginning.
Formatting the tablet
Select "Format system" then validate
Select "Reformat Device..." then validate
Finally choose "I understand" and validate
Once the formatting is finished, paste the firmware from your computer to your device at the root, as show below and validate