WinRM 服务无法处理该请求。具有客户端指定的命令 ID 的命令已存在答案

【问题标题】：The WinRM service cannot process the request. A command already exists with the command ID specified by the clientWinRM 服务无法处理该请求。具有客户端指定的命令 ID 的命令已存在
【发布时间】：2016-12-03 08:01:02
【问题描述】：

当我在 Visual Studio 2015 中调试时运行下面的代码时，它工作正常。当它部署到 IIS 时，我在第二个 ps.Invoke() 行收到以下错误：

WinRM 服务无法处理该请求。命令已存在使用客户端指定的命令 ID。

public static PowerShellResponse AddToDistributionGroup(Credentials creds, string groupName, string memberEmail)
{
    PSCredential cred = new PSCredential(creds.Username, creds.Password.ToSecureString());

    WSManConnectionInfo connectionInfo = new WSManConnectionInfo(new Uri(Settings.ExchangeServerAutomationUrl), Settings.ExchangeAutomationSchemaName, cred);
    connectionInfo.AuthenticationMechanism = AuthenticationMechanism.Kerberos;

    using (Runspace runspace = RunspaceFactory.CreateRunspace(connectionInfo))
    {
        using (PowerShell ps = PowerShell.Create())
        {
            runspace.Open();
            ps.Runspace = runspace;
            //can't pipe OU to Add-DistrubtionGroupMember b/c it blows up w/ "null reference exception" when member already exists

            var group =
                    ps
                        .AddCommand("Get-DistributionGroup")
                            .AddParameter("Identity", groupName)
                            .AddParameter("OrganizationalUnit", creds.GetUserDN())
                        .Invoke()
                        .SingleOrDefault();

            if (group == null)
                return new PowerShellResponse() { Errors = new List<string> { "Group not found." } };

            ps.AddStatement();

            ps.AddCommand("Add-DistributionGroupMember")
                .AddParameter("Identity", ((dynamic)group).Identity)
                .AddParameter("Member", memberEmail);

            ps.Invoke(); //this is where the error shows up

            return ps.GetResponse();
        }
    }
}

我正在使用 C# 和 PowerShell 3.0 连接到 Exchange（API 文档：https://technet.microsoft.com/en-us/library/dn641234(v=exchg.160).aspx），试图将成员添加到 Exchange 中的通讯组。

PowerShellResponse 是我们的自定义类，ps.GetResponse() 是自定义函数来创建说PowerShellResponse。

【问题讨论】：

标签： c# powershell exchange-server powershell-3.0

【解决方案1】：

由于无法在网上任何地方找到此错误，我想出的解决方案不是在一个 using 语句中调用 ps.Invoke() 两次。以下在本地和部署到 IIS 后都可以正常工作：

public static PowerShellResponse AddToDistributionGroup(Credentials creds, string groupName, string memberEmail)
{
    PSCredential cred = new PSCredential(creds.Username, creds.Password.ToSecureString());

    WSManConnectionInfo connectionInfo = new WSManConnectionInfo(new Uri(Settings.ExchangeServerAutomationUrl), Settings.ExchangeAutomationSchemaName, cred);
    connectionInfo.AuthenticationMechanism = AuthenticationMechanism.Kerberos;

    PSObject group;

    using (Runspace runspace = RunspaceFactory.CreateRunspace(connectionInfo))
    {
        using (PowerShell ps = PowerShell.Create())
        {
            runspace.Open();
            ps.Runspace = runspace;

            group =
                    ps
                        .AddCommand("Get-DistributionGroup")
                            .AddParameter("Identity", groupName)
                            .AddParameter("OrganizationalUnit", creds.GetUserDN())
                        .Invoke()
                        .SingleOrDefault();
        }
    }

    //can't pipe OU to Add-DistrubtionGroupMember b/c it blows up w/ "null reference exception" when member already exists
    if (group == null)
        return new PowerShellResponse() { Errors = new List<string> { "Group not found." } };

    using (Runspace runspace = RunspaceFactory.CreateRunspace(connectionInfo))
    {
        using (PowerShell ps = PowerShell.Create())
        {
            runspace.Open();
            ps.Runspace = runspace;

            ps.AddCommand("Add-DistributionGroupMember")
                .AddParameter("Identity", ((dynamic)group).Identity)
                .AddParameter("Member", memberEmail);

            ps.Invoke();

            return ps.GetResponse();
        }
    }
}

【讨论】：