Skip to main content

Processing attachments in a embedded email message

I had a question from someone today about how to process the attachments on a embedded email (basically when you get an email that has another email attached to it which has attachments). The basic code to process a set of attachments on a message in Ex2k look like this

set msg = createobject("cdo.message")
msg.datasource.open "file://./backofficestorage/domain.com/MBX/user/Inbox/Mess.EML"
set objattachments = msg.attachments
for each objattachment in objattachments
     objattachment.savetofile "d:\temp\" & objattachment.filename
next

If you have an email with a embedded email as an attachment this embedded email will appear in the attachment well of the the other email as content type message/rfc822 but the filename will be blank and the above code would fail to execute at this step. To process these type of messages you need to open the embedded message from the bodypart and then process the attachments on this message. The other problem now is that the depth of embedded email could be greater then just one so this is when some sort of function you can call recursively is really needed within your code. Embedded email extraction is covered in the Exchange SDK here . Here's some code to extract multiple depth attachments in a multiple embedded message.

set msg = createobject("cdo.message")
msg.datasource.open "file://./backofficestorage/domain.com/MBX/user/Inbox/Mess.EML"
set objattachments = msg.attachments
for each objattachment in objattachments
if objAttachment.ContentMediaType = "message/rfc822" then
procattach(objattachment)
else
objattachment.savetofile "d:\temp\" & objattachment.filename
end if
next
set msg = nothing

function procattach(objattachment)
set msg1 = createobject("cdo.message")
msg1.datasource.OpenObject objattachment, "ibodypart"
set objattachments1 = msg1.attachments
for each objattachment1 in objattachments1
if objAttachment1.ContentMediaType = "message/rfc822" then
procattach(objattachment1)
else
objattachment1.savetofile "d:\temp\" & objattachment1.filename
end if
next
set msg1 = nothing
end function



Popular posts from this blog

The MailboxConcurrency limit and using Batching in the Microsoft Graph API

If your getting an error such as Application is over its MailboxConcurrency limit while using the Microsoft Graph API this post may help you understand why. Background   The Mailbox  concurrency limit when your using the Graph API is 4 as per https://docs.microsoft.com/en-us/graph/throttling#outlook-service-limits . This is evaluated for each app ID and mailbox combination so this means you can have different apps running under the same credentials and the poor behavior of one won't cause the other to be throttled. If you compared that to EWS you could have up to 27 concurrent connections but they are shared across all apps on a first come first served basis. Batching Batching in the Graph API is a way of combining multiple requests into a single HTTP request. Batching in the Exchange Mail API's EWS and MAPI has been around for a long time and its common, for email Apps to process large numbers of smaller items for a variety of reasons.  Batching in the Graph is limited to a m
Read more

Sending a Message in Exchange Online via REST from an Arduino MKR1000

This is part 2 of my MKR1000 article, in this previous post  I looked at sending a Message via EWS using Basic Authentication.  In this Post I'll look at using the new Outlook REST API  which requires using OAuth authentication to get an Access Token. The prerequisites for this sketch are the same as in the other post with the addition of the ArduinoJson library  https://github.com/bblanchon/ArduinoJson  which is used to parse the Authentication Results to extract the Access Token. Also the SSL certificates for the login.windows.net  and outlook.office365.com need to be uploaded to the devices using the wifi101 Firmware updater. To use Token Authentication you need to register an Application in Azure https://msdn.microsoft.com/en-us/office/office365/howto/add-common-consent-manually  with the Mail.Send permission. The application should be a Native Client app that use the Out of Band Callback urn:ietf:wg:oauth:2.0:oob. You need to authorize it in you tenant (eg build a small ap
Read more

How to test SMTP using Opportunistic TLS with Powershell and grab the public certificate a SMTP server is using

Most email services these day employ Opportunistic TLS when trying to send Messages which means that wherever possible the Messages will be encrypted rather then the plain text legacy of SMTP.  This method was defined in RFC 3207 "SMTP Service Extension for Secure SMTP over Transport Layer Security" and  there's a quite a good explanation of Opportunistic TLS on Wikipedia  https://en.wikipedia.org/wiki/Opportunistic_TLS .  This is used for both Server to Server (eg MTA to MTA) and Client to server (Eg a Message client like Outlook which acts as a MSA) the later being generally Authenticated. Basically it allows you to have a normal plain text SMTP conversation that is then upgraded to TLS using the STARTTLS verb. Not all servers will support this verb so if its not supported then a message is just sent as Plain text. TLS relies on PKI certificates and the administrative issue s that come around certificate management like expired certificates which is why I wrote th
Read more
All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.