Attachment of work reference is uploaded and sent, when you click on it, it cannot be seen.
According to ETON spec the allowable file extensions are: .jpeg, .jpg, .jpe, .pdf, .dxf, .html, .htm, .docx and .odt
In other Phase details tab you can see the Attachment URL. In this case it had extension .msg
In order to view it, you need to save the document in the above allowable extensions and resend.