ContentId property specifies ID of the embedded attachment. ID is used to reference attachment in HTML body of e-mail message.
Syntax
[Visual Basic]
objMailAttachment.ContentId = "Img1"
[VBScript]
objMailAttachment.ContentId = "Img1"
[C#]
objMailAttachment.ContentId = "Img1";
[C++]
HRESULT get_ContentId(BSTR*);
HRESULT put_ContentId(BSTR);
spMailAttachment->PutContentId("Img1");
Remarks
Default value of ContentId property is an empty string. Application should set ContentId of the embedded attachments to be able to reference them in the HTML body of e-mail message. Please refer to the EmbeddedImages sample for details.