Does the "Send Later" feature on Exchange Online add any message headers?

%3CLINGO-SUB%20id%3D%22lingo-sub-2699668%22%20slang%3D%22en-US%22%3EDoes%20the%20%22Send%20Later%22%20feature%20on%20Exchange%20Online%20add%20any%20message%20headers%3F%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-2699668%22%20slang%3D%22en-US%22%3E%3CP%3EWith%20a%20relatively%20new%20Exchange%20Online%20feature%20allowing%20users%20to%20schedule%20delivery%20of%20a%20message%20with%20the%3CSPAN%3E%26nbsp%3B%3C%2FSPAN%3E%3CA%20href%3D%22https%3A%2F%2Fmspoweruser.com%2Fwp-content%2Fuploads%2F2020%2F06%2FOutlook-Send-Later.jpg%22%20target%3D%22_blank%22%20rel%3D%22nofollow%20noopener%20noreferrer%22%3E%22Send%20Later%22%20option%20on%20OWA%2C%3C%2FA%3E%3CSPAN%3E%26nbsp%3B%3C%2FSPAN%3Eis%20there%20any%20message%20headers%20that%20indicates%20when%20this%20feature%20was%20used%3F%20Or%20otherwise%20any%20way%20to%20have%20a%20transport%20rule%20detect%20a%20scheduled%20message%3F%26nbsp%3B%20I%20compared%20headers%20and%20could%20not%20find%20anything.%3C%2FP%3E%3CP%3ENote%20this%20is%20different%20than%20the%20scheduled%20delivery%20option%20in%20the%20MS%20Outlook%20client%20that%20has%20been%20around%20forever.%3C%2FP%3E%3CP%3EThanks!%3C%2FP%3E%3C%2FLINGO-BODY%3E%3CLINGO-LABS%20id%3D%22lingo-labs-2699668%22%20slang%3D%22en-US%22%3E%3CLINGO-LABEL%3EAdmin%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3EExchange%20Online%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3EOffice%20365%3C%2FLINGO-LABEL%3E%3C%2FLINGO-LABS%3E%3CLINGO-SUB%20id%3D%22lingo-sub-2712920%22%20slang%3D%22en-US%22%3ERe%3A%20Does%20the%20%22Send%20Later%22%20feature%20on%20Exchange%20Online%20add%20any%20message%20headers%3F%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-2712920%22%20slang%3D%22en-US%22%3EWhat%20exactly%20do%20you%20want%20to%20achieve%3F%20In%20other%20words%2C%20why%20do%20you%20need%20to%20detect%20a%20scheduled%20message%3F%3C%2FLINGO-BODY%3E
New Contributor

With a relatively new Exchange Online feature allowing users to schedule delivery of a message with the "Send Later" option on OWA, is there any message headers that indicates when this feature was used? Or otherwise any way to have a transport rule detect a scheduled message?  I compared headers and could not find anything.

Note this is different than the scheduled delivery option in the MS Outlook client that has been around forever.

Thanks!

5 Replies
What exactly do you want to achieve? In other words, why do you need to detect a scheduled message?

@Victor Ivanidze It's a customer request to prepend the message with a disclaimer.

Hi @IAD_Flyer,

do you mean that your customer wants that only scheduled messages have a disclaimer?  For what?

Correct. I believe it's related to concerns from HR about user time and attendance.

I doubt that's possible to do using any rule that analyzes the SMTP headers.
In case they definitely need this feature, they should be ready to pay for custom software development.