Menu
An application I am working on needs access to the headers of an email - specifically ones like return-path, in-reply-to, and references. Ideally, we would love to be able to access all of the RFC 2822 headers of the email. Is this possible with the Outlook/Office 365 REST API? If not, is it possible with any API?
768
Double-click an email message to open it outside of the Reading Pane. Click File > Properties. Header information appears in the Internet headers box. Tip: You can highlight the information in that box, press Ctrl+C to copy, and paste it into Notepad or Word to see the entire header at once.
With the email open in which you'd like to view the headers, click on the more actions drop down arrow in the top right corner, then select View Message Details.
Once you have an email message open in Gmail, click on the three-dot icon in the top-right hand corner of the message to expand the More menu. Click on Show original to see the raw email message with its full contents and header revealed.
Office 365 / Outlook Web Access (OWA) / Exchange 2016 In Outlook Web Access or Exchange 2016, in the email for which you want to view headers, click the down arrow. This icon is located next to Reply or Reply all in the upper-right corner. Click View message details. Review the email header information that appears.
UPDATE: The InternetMessageHeaders property was added to the beta endpoint of the Outlook API, so you can get this without using the extended property stuff. You do have to request the property explicitly via $select though. Something like:
GET https://outlook.office.com/api/beta/me/mailfolders/inbox/messages?
$select=Subject,InternetMessageHeaders
For Graph: The property also exists on messages in the beta endpoint for Graph, so you can do:
GET https://graph.microsoft.com/beta/me/mailfolders/inbox/messages?
$select=subject,internetMessageHeaders
For non-beta endpoints: The API doesn't directly provide access. However, you can access the PidTagTransportMessageHeaders MAPI property using the Extended Property API.
From the first link, we see that the property ID for PidTagTransportMessageHeaders is 0x7D, and the type is String. So the $expand parameter of your GET would look like:
$expand=SingleValueExtendedProperties($filter=PropertyId eq 'String 0x7D')
NOTE: This is only applicable for the Outlook endpoint (https://outlook.office.com). For Graph, see the answer from madsheep
Putting that together with a GET for a specific message, your request might look like:
GET https://outlook.office.com/api/v2.0/me/messages/{message-id}?
$select=Subject,SingleValueExtendedProperties
&$expand=SingleValueExtendedProperties($filter=PropertyId eq 'String 0x7D')
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
