If you are building a website, specifically an ashx "processRequest" .net and have setup your local pc to have its own name in the hosts file like mysite.local edit c:\windows\system32\drivers\etc\hosts and make sure the entry for mysite.local is linked to the correct ipconfig ipaddress.

Now the reason for a hosts entry is so you can create a self signed cert for mysite.local so you can test https from the visual studio debugger.