Fixing Bad Request (Invalid Hostname)” - 400 Error

Solution:

This issue usually occurs when the configuration is not done properly at the client side (IIS Server).

Open IIS Manger, from the Web Sites, select the site for which the error is generated.

Right click and select properties, from under the Web Site tab choose advanced and check if the IP address is set to (All Unassigned), and also check if the port and header are configured properly.

This should rectify this error