ASP.NET web application is not working with localhost in the URL on IE11 in Windows 8.1

I have a .net web application. I am unable to open the application using localhost in URL. Error is : Mozilla/5.0 (Windows NT 6.3; WOW64; Trident/7.0; rv:11.0) like Gecko Unsupported Browser Type

Then I modified code to recognize UA String as

bVal = (Regex.IsMatch(context.Request.UserAgent, "(?i:msie (?:7|8|9)\.)")) || Regex.IsMatch(context.Request.UserAgent, @"Trident/7.*");

Then it is opened but I can not perform any action. Where as it is working fine when I open with Machine name in URL.

The above scenario is in Windoows 7 and IE11.

In windows 8.1 and IE11, still I am getting the same error even after modifying UA String.

Thanks in advance.