The following is the fix for the error “HTTP Error 400. The request hostname is invalid” when trying to browse an IIS Express site using a different host name or IP address.
1. Exit the IIS Express instant currently running.
2. Open IIS Express’s applicationhost.config located at the following path C:\Users\<user>\Documents\IISExpress\config\applicationhost.config
3. Find the entry for a particular site (e.g “Test” running in port 6306) which you are developing.
e.g.
<site name="FlickrTest" id="10">
<application path="/" applicationPool="Clr4IntegratedAppPool">
<virtualDirectory path="/" physicalPath="E:\Projects\BB Apps\FlickrTest" />
</application>
<bindings>
<binding protocol="http" bindingInformation="*:6306:localhost" />
</bindings>
</site>4. Replace the following
bindingInformation=”*:6306:localhost” with bindingInformation=”*:6306:*”
5. Save the file.
6. Start a command prompt in administrator mode and run the following command.
netsh http add urlacl url=http://*:6306/ user=Everyone
7. Now debug the site again and you should be able to access the url using IP address or host name.