Du kannst ein Mime- Item hierzu "missbrauchen" (siehe diesen Best Practice Artikel (https://atnotes.de/index.php?topic=52040.0)):
Dim stream as NotesStream
Dim ses as New NotesSession
Dim db as NotesDatabase
Dim doc as NotesDocument
Dim mimeent as NotesMimeEntity
Dim strEncodedFile as String
Set db = ses.CurrentDatabase
Set stream = ses.CreateStream()
call stream.Open( PathToYourAttachment )
Set doc=New NotesDocument(db)
Set miment=doc.CreateMIMEEntity
Call miment.SetContentFromBytes(stream, "", ENC_IDENTITY_BINARY)
Call miment.EncodeContent(ENC_BASE64)
strEncodedFile =miment.ContentAsText()