ASP.NET Web API returns 404 for PUT only on some servers

For those of you who do not have WebDAV enabled but are still running into this issue using MVC 4’s Web API’s… Steve Michelotti documented a solution that worked for me here. At the end of the day, I enabled all verbs (verb=”*”) to the ExtensionlessUrlHandler-Integrated-4.0 handler in my web config. <system.webServer> <validation validateIntegratedModeConfiguration=”false” /> … Read more

Unable to authenticate to ASP.NET Web Api service with HttpClient

I have investigated the source code of HttpClientHandler (the latest version I was able to get my hands on) and this is what can be found in SendAsync method: // BeginGetResponse/BeginGetRequestStream have a lot of setup work to do before becoming async // (proxy, dns, connection pooling, etc). Run these on a separate thread. // … Read more

401 response for CORS request in IIS with Windows Auth enabled

You can allow only OPTIONS verb for anonymous users. <system.web> <authentication mode=”Windows” /> <authorization> <allow verbs=”OPTIONS” users=”*”/> <deny users=”?” /> </authorization> </system.web> According W3C specifications, browser excludes user credentials from CORS preflight: