TIdAttachment in Indy10

Giganews Newsgroups
Subject: TIdAttachment in Indy10
Posted by:  Arch (archie.campbe…@ed.ac.uk)
Date: Wed, 12 Aug 2009

I have been using Indy10 mail messages in Delphi v10 quite happily but never
tried sending an attachment before.
I thought it would go something like...
uses IdAttachment

var attach: TIdAttachment;

attach := TIdAttachment.Create(mailmsg.MessageParts);
attach.FileName := fname;

But this gives me an Astract Error.
mailmsg sends OK without the attachment (which is just a plain text file)
Any help gratly appreciated