我有一个 WCF 服务，我需要在 IIS 7.5 上托管的 ASP.NET Web 应用程序中调用它。此 WCF 服务使用客户端证书的传输安全性。我获得了一个客户端证书，我使用 mmc 在“本地计算机/个人”存储位置安装了该证书。.pfx 安装了 2 个其他证书（无私钥），它们是我的带有私钥的客户端证书的 CA。我在运行时分配证书，因为将来我可能会将其他证书用于相同的 Web 服务。
wcfClient.ClientCredentials.ClientCertificate.SetCertificate(StoreLocation.LocalMachine, StoreName.My, X509FindType.FindBySerialNumber, "XXXXXXXXXXXXXXXXXXXXXX");
// debugging shows that client certificate was found
var result = wcfClient.CallMyMethod();
对于在 ApplicationPoolIdentity 下运行的 Web 应用程序，调用 Web 服务会引发带有内部 WebException（403 禁止）的 MessageSecurityException，就好像我根本没有通过客户端证书一样。如果配置需要，实际上不设置有效证书将通过 InvalidOperationException。如果我在管理员帐户下运行，则不会引发异常。我需要能够调用 ApplicationPoolIdentity 下的 web 服务。
编辑：我认为证书链可能是这里的问题......
到目前为止我已经尝试过：
- 在 MMC 中：MyCertificate -> All Tasks -> Manage Private Keys... 我授予 IIS_IUSRS 管理私钥的权限
- 为 C:\ProgramData\Microsoft\Crypto\RSA 添加了对 IIS_IUSRS 的读取访问权限
- 我使用了 System.Net 跟踪，并比较了 ApplicationPoolIdentity 和我的管理员帐户的日志。在“我们有用户提供的证书。服务器已指定 24 个颁发者。寻找与任何颁发者匹配的证书。 ”行之后，一切看起来都一样，直到下面的某个点。
ApplicationPoolIdentity 日志：
System.Net Information: 0 : [5436] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=0, returned code=CredentialsNeeded).
System.Net Information: 0 : [5436] SecureChannel#20350898 - We have user-provided certificates. The server has specified 24 issuer(s). Looking for certificates that match any of the issuers.
System.Net Information: 0 : [5436] SecureChannel#20350898 - Left with 0 client certificates to choose from.
System.Net Information: 0 : [5436] Using the cached credential handle.
System.Net Information: 0 : [5436] InitializeSecurityContext(credential = System.Net.SafeFreeCredential_SECURITY, context = fc5d070:1ffd1d0, targetName = ws.allianztiriac.ro, inFlags = ReplayDetect, SequenceDetect, Confidentiality, AllocateMemory, InitManualCredValidation)
System.Net Information: 0 : [5436] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=349, returned code=ContinueNeeded).
System.Net Information: 0 : [5436] InitializeSecurityContext(credential = System.Net.SafeFreeCredential_SECURITY, context = fc5d070:1ffd1d0, targetName = ws.allianztiriac.ro, inFlags = ReplayDetect, SequenceDetect, Confidentiality, AllocateMemory, InitManualCredValidation)
System.Net Information: 0 : [5436] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=0, returned code=ContinueNeeded).
System.Net Information: 0 : [5436] InitializeSecurityContext(credential = System.Net.SafeFreeCredential_SECURITY, context = fc5d070:1ffd1d0, targetName = ws.allianztiriac.ro, inFlags = ReplayDetect, SequenceDetect, Confidentiality, AllocateMemory, InitManualCredValidation)
System.Net Information: 0 : [5436] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=0, returned code=OK).
System.Net Information: 0 : [5436] Remote certificate: [bla bla remote certificate]
System.Net Information: 0 : [5436] SecureChannel#20350898 - Remote certificate was verified as valid by the user.
管理员帐户日志：
System.Net Information: 0 : [5952] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=0, returned code=CredentialsNeeded).
System.Net Information: 0 : [5952] SecureChannel#60080036 - We have user-provided certificates. The server has specified 24 issuer(s). Looking for certificates that match any of the issuers.
System.Net Information: 0 : [5952] SecureChannel#60080036 - Selected certificate: [Bla bla bla client cert info]
System.Net Information: 0 : [5952] SecureChannel#60080036 - Left with 1 client certificates to choose from.
System.Net Information: 0 : [5952] SecureChannel#60080036 - Trying to find a matching certificate in the certificate store.
System.Net Information: 0 : [5952] SecureChannel#60080036 - Locating the private key for the certificate: [Bla bla bla client cert info]
System.Net Information: 0 : [5952] SecureChannel#60080036 - Certificate is of type X509Certificate2 and contains the private key.
System.Net Information: 0 : [5952] AcquireCredentialsHandle(package = Microsoft Unified Security Protocol Provider, intent = Outbound, scc = System.Net.SecureCredential)
System.Net Information: 0 : [5952] InitializeSecurityContext(credential = System.Net.SafeFreeCredential_SECURITY, context = 4e5bb48:1fff710, targetName = ws.allianztiriac.ro, inFlags = ReplayDetect, SequenceDetect, Confidentiality, AllocateMemory, InitManualCredValidation)
System.Net Information: 0 : [5952] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=5718, returned code=ContinueNeeded).
System.Net Information: 0 : [5952] InitializeSecurityContext(credential = System.Net.SafeFreeCredential_SECURITY, context = 4e5bb48:1fff710, targetName = ws.allianztiriac.ro, inFlags = ReplayDetect, SequenceDetect, Confidentiality, AllocateMemory, InitManualCredValidation)
System.Net Information: 0 : [5952] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=0, returned code=ContinueNeeded).
System.Net Information: 0 : [5952] InitializeSecurityContext(credential = System.Net.SafeFreeCredential_SECURITY, context = 4e5bb48:1fff710, targetName = ws.allianztiriac.ro, inFlags = ReplayDetect, SequenceDetect, Confidentiality, AllocateMemory, InitManualCredValidation)
System.Net Information: 0 : [5952] InitializeSecurityContext(In-Buffers count=2, Out-Buffer length=0, returned code=OK).
System.Net Information: 0 : [5952] Remote certificate: [bla bla bla remote certificate]