Not able to make virtual instance using bridge network mode

Hi All,
I am facing problems.
I am trying to setup a demo ERPNext instance from the virtualbox download image.
My intention is to use virtual box, and the instance network instance to be on bridge mode, than the default NAT.
Keeping on bridge mode I can give access to others who are in the network to the erp instance, from their PC, by opening http//:IP-address:8080
In the present image properties, If I change the network setting to bridge I cannot access it

Advice requested for making it to work in the bridge mode
Thanks
Joseph John