Unknown error in Enterprise Gateway

Hi,

I am configuring the power bi enterprise gateway for one of my client at their server. While installing it doesnt show any error and gives me that setup was successful log on to configure the gateway. I am able to log in then create a gateway it gives me a succesful message saying gateway is good to go.

Then when I click close and add Data source button it directs me to the Browser as it should now there the gateway seems to through me an Unknown error. 

Below is the screen shot of the same.

Can anyone help with this as its kind of urgent requirement.