If you are receiving a 404 error while accessing your custom domain, as shown in Figure 1, then you are most likely missing the link between your Windows Azure Web Site configuration and your custom domain.

Before we move to the solution, you might want to also check these descriptions of how to map a custom domain to a Windows Azure Web Site found here and here.  Make sure you have followed all those instruction carefully.

 

To resolve this issue, access the Windows Azure management console here and click on the WAWS you are trying to link the custom domain to.  Once there, click the CONFIGURE link as illustrated in Figure 2.

Figure 2, the CONFIGURE link for a given WAWS

Scroll down until you find the Manage Domains button as shown in Figure 3.

Figure 3, Manage Custom domains for a Windows Azure Web Site

Clicking on the Manage Domains button will render a pop-up box that resembles Figure 4.

Figure 4, Manage custom domains for a Windows Azure Web Site

Enter in your custom domain and the 404 issue should be resolved in a number of seconds.  If the issue remains or you get a pop-up error stating “The DNS record for ‘’ that points to ‘’ could not be located”, go back and review the entire configuration using the 2 links provided at the beginning of this article.

You might also want to check the WAWS forums for additional help location here.

UPDATE 12-MAY-2014:

When this happens suddenly, check the mode of your Web Site, I.e. Free, Shared, Basic or Standard.  If your subscription gets suspended, your sites are set to Free mode and your custom domain setting is not valid in that mode.

UPDATE 29-JAN-2014:

Another reason I have found that this issue can exist is that the mapping of custom domains is only supported (when writing this) when the web site is running in either Shared, Basic or Standard mode.  I had a WAWS (Windows Azure Web Site) in Standard mode and mapped a custom domain to it.  At a later point I scaled the mode down to Free for some reason and my custom domain stopped working and I got the 404 file or directory not found.

I scaled the Windows Azure Web Site back to Standard mode and the custom domain worked seconds later.

Setting up a custom domain requires changes to your DNS configuration, for example CNAME an A Record settings.  Once you make all these configurations, if it still doesn't work (and you are getting a 404) make sure your WAWS is at the supported scale mode.