这里的其他答案都很好，但也有一个替代方案：
Attachment.GetTemporaryFilePath Method (Outlook)
Attachment.SaveAsFile Method (Outlook)

检索路径

var attachment = contact.Attachments["ContactPicture.jpg"] as Attachment;
var path = attachment.GetTemporaryFilePath();

保存文件

var attachment = contact.Attachments["ContactPicture.jpg"] as Attachment;
var path = attachment.SaveAsFile(savePath);

根据您的使用情况，如果您试图从他们的Outlook配置文件中获取他们的图片，您可能需要尝试Graph API。
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