Problem while sending atatchement as excel file in SOAP request

I want to attach an excel file in soap request, I tried Using cid:notation, and base64, both is getting failed.

In attachment pane , when I  choose the unique-identifier that was specified with the cid: notation in payload, the TYPE column should not be changing as"CONTENT". It is showing as "XOP"  and the content-type is showing as "application/octet-stream"

I don't know what is the issue

Please help me on this, Let me know if any other details are required.

Please let me know if any other details are required. I am using free version of soapUI 5.2.0. I am new to SOAP UI.

Thanks & Regards,

Murugan Chelliah