Download Android Jelly Bean 4.2.2 stock firmware for Vido M6C / YuanDao M6C tablet from here or from here. Download previous firmware version from here. Download another Yuandao firmware from here.
Archive: M6C-4.2-20141104-ZZ.zip
Model: Vido M6C / YuanDao M6C tablet ZZ model
Image file size: 250 MB
Platform: Intel Atom Z2520