TextWatermarkwatermark=newTextWatermark("Test watermark",newFont("Arial",19));EmailLoadOptionsloadOptions=newEmailLoadOptions();// Specify an absolute or relative path to your document. Ex: @"C:\Docs\message.msg"using(Watermarkerwatermarker=newWatermarker("message.msg",loadOptions)){EmailContentcontent=watermarker.GetContent<EmailContent>();foreach(EmailAttachmentattachmentincontent.Attachments){// Check if the attached file is supported by GroupDocs.WatermarkIDocumentInfoinfo=attachment.GetDocumentInfo();if(info.FileType!=FileType.Unknown&&!info.IsEncrypted){// Load the attached documentusing(WatermarkerattachedWatermarker=attachment.CreateWatermarker()){// Add wateramrkattachedWatermarker.Add(watermark);// Save changes in the attached fileattachedWatermarker.Save();}}}// Save changeswatermarker.Save("message.msg");}