使用Graph API从共享邮箱发件时无法保存至Sent Items文件夹

我们通过Entra应用身份验证，使用Graph API读取并从共享邮箱发送邮件，但发送的邮件无法保存到该共享邮箱的“已发送邮件”文件夹。除该问题外，其余功能均正常：收件人可正常收到邮件，发件人地址也正确设置为共享邮箱地址。

Entra权限 #

技术环境 #

ASP.NET应用，使用5.56.0版本的Microsoft.Graph NuGet包。

代码实现 #

初始化GraphServiceClient代码 #

private async Task<GraphServiceClient> InitGraphServiceClient()  
{  
    var clientSecret = await GetClientSecret();  
    var settings = graphSettings.Value;  
    var credential = new ClientSecretCredential(settings.TenantId, settings.ClientId, clientSecret);  
    return new GraphServiceClient(credential, ["https://graph.microsoft.com/.default"]);  
}

发送邮件代码 #

// ... 上方代码省略
var fromAddr = "<shared-mailbox-email-address>"; // 从配置注入
var requestBody = new SendMailPostRequestBody{  
    Message = new Message  
    {  
        Subject = subject,  
        Body = new ItemBody  
        {  
            ContentType = BodyTypeToGraphApiBodyType(bodyType),  
            Content = body  
        },  
        ToRecipients = new List<Recipient>  
        {  
            new()  
            {  
                EmailAddress = new EmailAddress  
                {  
                    Address = to  
                },  
            },  
        },  
        Attachments = attachments.Select(  
                a => new FileAttachment  
                {  
                    OdataType = "#microsoft.graph.fileAttachment",  
                    ContentBytes = Convert.FromBase64String(a.Base64Content),  
                    Name = a.Name,  
                    ContentType = a.ContentType,  
                } as Microsoft.Graph.Models.Attachment  
            )  
            .ToList()  
    },  
    SaveToSentItems = true  
};  
var graphServiceClient = await graphServiceClientProvider.GetGraphServiceClientAsync();  
await graphServiceClient.Users[fromAddr].SendMail.PostAsync(requestBody);

已尝试的解决方案 #

• 在请求体中添加From和/或Sender属性
• 移除SaveToSentItems = true设置

以上两种方案均无效，寻求解决该问题的方法。

内容的提问来源于stack exchange，提问作者RossM