HTTP Error 503 - But only when using domain name to navigate

Question

I am currently having a strange issue that has taken me by surprise, I have not had the issue before and I have no idea why I am getting it now.

I have an asp.net mvc 3 website which has a number of controllers all with actions. It is important to note that this issue is only present with one controller and the problem is with all Actions.

The error I am getting is "HTTP Error 503. The service is unavailable."

However, this error only occurs if I browse to the page using the domain name, for example...

subdomain.example.com/controller

but everything works fine if I browse with the ip address and port number...

xxx.xxx.xxx.xxx:xxxxx/controller

remember all other controllers work fine regardless of the method used to browse.

I have tried looking for answers to this and trying to find any useful logging information but have found nothing of use. Hopefully somebody here will have seen this issue before

Answer 1

Ok I have created a sample mvc project with a Reports controller that works so I don't believe it is a problem with MVC.

I'd reccomend looking at your routes and your web.config and make sure you don't have anything intercepting it there into an httphandler or module. Then I'd look at the IIS instance and check for virtual directories. You pretty much are trying to figure out where exactly it is failing - is it even reaching ASP.Net?

One last option to look into is your company proxy - does going to the URL directly go through the proxy? I know at my company this can happen - so there may be a rule there that is intercepting it.