ASP.NET Custom error page for 404 returns 302 for http status

Question

In my asp.net web site I have custom error pages defined as following in my web.config file.

Answer 1

After Googling about this issue, it seems that this is the default behavior that Microsoft ASP.NET provides for the situation. This is very bad for SEO. A work around I found is to check whether the requested file exists in an HTTP handler (or global.asax file), or use:

If the requested file does not exist, then rewrite the request path to a file not found page (if using an HTTP handler or global.asax), clear the server errors on the 404 error page code behind, and add a 404 error header to the response manually rather than waiting for server to do so.

Server.ClearError();
Response.Status = "404 Not Found";
Response.StatusCode = 404;