I've seen lots of discussion on this but no answers. I have an addin (VB.NET and VSTO) that strips attachements from emails as they are sent. Trouble is, I don't want to strip attachement (usually images) that are within the body of the message. I quite often paste images from the clipboard into my HTML messages and these need to be retained. So when looping through the attachments in a message how can you robustly check if the attachment is embedded or not? Based on other articles I've seen I thought something like this might work by actually oAttachments.Type doesn't seem to be any different between an attached XLS file and an embedded JPG file. Private Function HasNonEmbeddedAttachements() As Boolean Dim retval As Boolean = False Dim oAttachment As Outlook.Attachment If m_olMailItem.Attachments.Count = 0 Then retval = False Else For Each oAttachment In m_olMailItem.Attachments If oAttachment.Type = Outlook.OlAttachmentType.olByValue Then retval = False Else retval = True Exit For End If Next End If Return retval End Function