When deploying a single html page on a Windows Azure web app, I noticed some of the default IIS behaviors for ASP.Net still apply, even if there is no actual ASP.Net application deployed on the server. The specific case I don't understand is if the client enter an invalid addresss like https://www.mysuperwebsite.com/>. By default, IIS consider this address as unsecure (more info here and here), which is totally fine to me.
The problem I have from that point is I want to display my own error page, not the default one from IIS.
As my site contains no ASP.Net related stuff, I was on the impression that only the httpErrors section of the web.config applies in my case. But with the following config, I wasn't able to display my error page:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<system.webServer>
<httpErrors errorMode="Custom" defaultResponseMode="File" defaultPath="error.html">
<remove statusCode="400"/>
<error statusCode="400" responseMode="File" path="error.html"/>
</httpErrors>
</system.webServer>
</configuration>
The only way I got it to work was by adding the next section:
<system.web>
<customErrors mode="RemoteOnly" defaultRedirect="error.html" />
</system.web>
But from my understanding customErrors section is dediacted to handle errors generated by ASP.Net code, which I don't have in my case...
- I confirmed with postman the error code returned by IIS in that case is 400 - bad request.
- I also tested my error paged configured in
httpErrorsby creating a folder on the web app and trying to list its content: in that case thehttpErrorssection is driving the displayed error page. - Files for simple reproduction available here.
