Email Attachment’s filename

I can successfully pick up a file and send it as an email attachment. But the attachment’s filename is ’Attachment’, when double click to save it, it will default save the file as name “TestLocationNZCMAN000000000804.TXT”, in which “TestLocationNZC” is the path for the pick up file, and MAN000000000804.TXT is the original file name.

I didn’t use custom pipeline, (I tried but don’t know even if read the “ReceivedFileName” then how to reference it in orchestration)

Instead, I created one String Variable “OriginalFN” in Orchestration, in one Expression shape I added the following code: OriginalFN=ReceivedMessageType(FILE.ReceivedFileName);

Then in an message assignment shape:
//setup email attachment and content type, MSGtoSend is the multipart message to send
MSGtoSend.Attachment= ReceivedMessageType;
SMTPUtils.Part.SetContentType(MSGtoSend.Attachment, \”text/xml\”);
SMTPUtils.Part.SetFileName(MSGtoSend.Attachment,OriginalFN);

I’m wondering how to make the attachment read as the original file name. Any thoughts and suggestion? Thanks in advance.

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BTW,
In my custom pipeline I used coding like this:
public IBaseMessage Execute(IPipelineContext pc, IBaseMessage inmsg)

{
const string FILEadapterTargetNamespace = \”http://schemas.microsoft.com/BizTalk/2003/file-properties\”;
string sourcePath = inmsg.Context.Read(\”ReceivedFileName\”, FILEadapterTargetNamespace ) as string;

return inmsg;

}
But I didn’t implement IDisassemberComponent, and when I put it under Pipeline Disassemble, it gives error to let me implement this interface. Also I don’t know how to reference the “ReceivedFileName” in orchestration.