WCF - AccessDeniedException HTTP could not register URL

I was fooling around with WCF today and started getting the following exception:

AddressAccessDeniedException: HTTP could not register URL http://+:8370/TestService/. Your process does not have access rights to this namespace.

The problem is pretty simple, but it took me a little while to figure out. To host the WCF service, you need to have the ability to register the URL. I run visual studio as a non-administrator, and this requires administrator privileges.

But wait just one second, this service was running fine just a couple minutes ago and I didn't have administrator privileges then. How did that work? Well, it seems that VS automatically registers any URLs in the form of http://[server]:[port]/Design_Time_Addresses/[Rest of Service Url] which allows them to be hosted.

So, I was trying to be too fancy and I was trying to change the URL to get rid of the "Design_Time_Addresses" part of the URL. I added that back to the URL and I was able to host the service again.

If you want to host the URL without the "Design_Time_Addresses" bit, you will have to register (as admin) the URL. Follow the link in the exception details to see how to register the URL.