Cannot access home menu and system setting - Android 4 TV Box

[AC Question]

I have an Android 4.0 TV Box, worked fine, one day, after boot up, the screen went blank and no response, however, when I connected a USB keyboard to it, I can launch the browser, access apps through playstore and seems like all the apps are working.

I see an app "mbui" when I hit alt-tab, that seems like the home user interface which is corrupted or not working.

Is there anyway I can restore the home menu ? I have access to ES Explorer and can edit file but do not have root access

Thanks in advance