Accessing an email attachment as an object - vbscript

Question

OK so I have a script that goes through my outlook inbox looking for a particular header string. This works great for emails directly in my inbox. Now I'm trying to expand this detection to emails that contain other emails as attachments. I've spent significant time researching this and I can't seem to find the proper way to access the email attachment directly. What I've ended up doing is saving the attachment to disc and then reading it back in using CreateItemFromTemplate. I find this to be a cludge solution and I'm hoping someone here can help me find a more elegant way to do this where I can bypass the saveas as CreateItemFromTemplate and directly create an item object from the attachment. Here is proof of concept script I've put together for this:
Const olFolderInbox = 6
Const olMail = 43
Const olEmbeddeditem = 5
Const PropName = "http://schemas.microsoft.com/mapi/proptag/0x007D001E"
Set app = CreateObject("Outlook.Application")
set objNamespace = app.GetNamespace("MAPI")
set objInboxItems = objNameSpace.GetDefaultFolder(olFolderInbox).items
wscript.echo "Have your inbox open checking for fish tests or emails as attachments"
for each objItem in objInboxItems
if objItem.Class = olMail then
with objItem
strHeader = .PropertyAccessor.GetProperty(PropName)
iLoc1 = instr(1,strHeader,"X-Testing",1)
if iLoc1 > 0 then
wscript.echo "mytest. From: " & .Sender & " at: " & .ReceivedTime & " subjet: " & .Subject
end if
iLoc1 = instr(1,strHeader,"X-PHISHTEST",1)
if iLoc1 > 0 then
wscript.echo "Go Fish. From: " & .Sender & " at: " & .ReceivedTime & " subjet: " & .Subject
end if
if .attachments.count > 0 then
set objAttachment = .attachments.item(1)
if objAttachment.type = olEmbeddeditem then
wscript.echo "Has Attachment. From: " & .Sender & " at: " & .ReceivedTime & " subjet: " & .Subject
wscript.echo " - Filename: " & objAttachment.Filename
objAttachment.SaveAsFile ("c:\temp\TempEmail.msg")
set objExtMsg = app.CreateItemFromTemplate("c:\temp\TempEmail.msg")
strExtHeader = objExtMsg.PropertyAccessor.GetProperty(PropName)
iLoc1 = instr(1,strExtHeader,"X-Testing",1)
if iLoc1 > 0 then wscript.echo " ++ This is a plain test message"
end if
end if
end with
end if
next
wscript.echo "That's all folks" `

Answer 1

That is the best you can do in OOM alone - save the attachment as an MSG file and then reopen it. OpenSharedItem is a better way to open an MSG file than CreateItemFromTemplate.
On the Extended MAPI level (C++ or Delphi), you can open the PR_ATTACH_DATA_OBJ property as IMessage using IAttach::OpenProperty. If Extended MAPI is not an option, you can use Redemption (I am its author - any language) - both Safe*Item and RDO families of objects expose EmbeddedMsg property on the attachment object that return the attachment message.