我在从 C# 客户端调用 Web 服务时遇到了一些问题。有时它会返回以下错误：
WWW-Authenticate: Basic realm="[SomeRealm]"'. --->
System.ServiceModel.Security.MessageSecurityException:
The HTTP request is unauthorized with client authentication scheme 'Digest'.
The authentication header received from the server was 'Digest realm="[SomeRealm]",
nonce="00000717Y382188758809db0bcc622bdf37def3deabb93", stale=FALSE, qop="auth"
WWW-Authenticate: Basic realm="[SomeRealm]"'. --->
System.Net.WebException: The remote server returned an error: (401) Unauthorized.
但我不知道为什么，它真的很难重现，因此调试起来非常棘手。大多数时候，对 Web 服务的调用工作得很好。有人知道为什么会这样吗？或者有关如何调试和获取有关该问题的更多信息的任何提示？
更新：
好的，所以我尝试查看使用 fiddler 进行的通信，但这并没有让我变得更聪明。
这是一个有效的请求/挑战/请求/响应
要求
POST http://192.168.1.3/api/services HTTP/1.1
Content-Type: application/soap+xml; charset=utf-8;
action="http://www.domain.com/api/ws/event1/GetScheduledEvents"
Host: 192.168.1.3
Content-Length: 482
Accept-Encoding: gzip, deflate
Connection: Keep-Alive
挑战
HTTP/1.1 401 Unauthorized
Date: Wed, 14 Aug 2013 07:45:49 GMT
Accept-Ranges: bytes
Connection: close
WWW-Authenticate: Digest realm="[SomeRealm]",
once="00025a89Y1892894c7fb9fe5f9de425b40c72d72de3227", stale=FALSE, qop="auth"
WWW-Authenticate: Basic realm="[SomeRealm]"
Content-Length: 180
Content-Type: text/html; charset=ISO-8859-1
<HTML><HEAD><TITLE>401 Unauthorized</TITLE></HEAD>
<BODY><H1>401 Unauthorized</H1>
Your client does not have permission to get URL /api/services from this server.
</BODY></HTML>
要求
POST http://192.168.1.3/api/services HTTP/1.1
Content-Type: application/soap+xml; charset=utf-8; action="http://www.domain.com/api/ws/event1/GetScheduledEvents"
Accept-Encoding: gzip, deflate
Authorization: Digest username="UserName",realm="[SomeRealm]",nonce="00025a89Y1892894c7fb9fe5f9de425b40c72d72de3227",uri="/api/services",cnonce="abff70e14c8f89b09abac9eaaa9de8ce",nc=00000001,qop="auth",response="df71769f9fb2bb5e1396546b7422d5fd"
Host: 192.168.1.3
Content-Length: 482
Connection: Keep-Alive
回复
HTTP/1.1 200 OK
Authentication-Info: qop=auth, rspauth="51832dfe63819c551bf666409f58b08c", cnonce="abff70e14c8f89b09abac9eaaa9de8ce", nc=00000001
Server: gSOAP/2.7
Content-Type: application/soap+xml; charset=utf-8
Content-Length: 3752
Connection: close
这是失败的请求/挑战/请求/响应之一
要求
POST http://192.168.1.3/api/services HTTP/1.1
Content-Type: application/soap+xml; charset=utf-8; action="http://www.domain.com/api/ws/event1/GetScheduledEvents"
Host: 192.168.1.3
Content-Length: 482
Accept-Encoding: gzip, deflate
Connection: Keep-Alive
挑战
HTTP/1.1 401 Unauthorized
Date: Wed, 14 Aug 2013 07:45:49 GMT
Accept-Ranges: bytes
Connection: close
WWW-Authenticate: Digest realm="[SomeRealm]", nonce="00025a89Y3757607d2e481c5c24cb20f1a46b129a37218", stale=FALSE, qop="auth"
WWW-Authenticate: Basic realm="[SomeRealm]"
Content-Length: 180
Content-Type: text/html; charset=ISO-8859-1
<HTML><HEAD><TITLE>401 Unauthorized</TITLE></HEAD>
<BODY><H1>401 Unauthorized</H1>
Your client does not have permission to get URL /api/services from this server.
</BODY></HTML>
要求
POST http://192.168.1.3/api/services HTTP/1.1
Content-Type: application/soap+xml; charset=utf-8; action="http://www.domain.com/api/ws/event1/GetScheduledEvents"
Accept-Encoding: gzip, deflate
Authorization: Digest username="UserName",realm="[SomeRealm]",nonce="00025a89Y3757607d2e481c5c24cb20f1a46b129a37218",uri="/api/services",cnonce="9daae13f56820d9edf12cbf7e41f894b",nc=00000001,qop="auth",response="18d885af71eb74d1476da0f3668bf00e"
Host: 192.168.1.3
Content-Length: 482
Connection: Keep-Alive
回复
HTTP/1.1 401 Unauthorized
WWW-Authenticate: Digest realm="[SomeRealm]", nonce="00025a89Y412766b2f55e4fc54dbd441b95cc713e08ccb", stale=FALSE, qop="auth"
WWW-Authenticate: Basic realm="[SomeRealm]"
Server: gSOAP/2.7
Content-Type: text/xml; charset=utf-8
Content-Length: 0
Connection: close