I believe this is yet another new unexpected (or at least not well published) change on Microsoft's side ...unless I am completely obtuse and missed it before now. But this is the reference article explaining this new requirement for attachments over 3 MB:
Attach Large Files to Outlook Messages or Events

...Also, since we do not rely on the presence of a local Outlook install, this I think may have been misleading even if it has been there all along - not too surprising either way given MS track record :/

Nevertheless, we have implemented the Auth Code flow for oauth using MS Graph API in our application, using the EASendMail ActiveX components (for Delphi) and it has been working great for a while now. I believe EASM v7.8 is the latest we have implemented.
Only recently have we started to get support requests because our users are starting to see this error in the failed mail send response:
ERROR: Failed to send email with error: (osmtp err code:13) Error with MsGraph Api; 413 Request Entity too large

Our SQA team has also tested using large files as well as a list of several files (with cumulative size) over 3MB many times prior to release, so this also makes me think it is a new thing from MS.

SO! My question: Is this something the team is aware of, and can we expect to see this issue addressed in an update in the near future?

My concern is that I would prefer that our team does not have to write the code for this manually, as that seems like it would also mean writing the code for the rest of the process as well. Which, of course, negates the whole reason we purchased the EASendMail product - all the moving parts are built-in, it is convenient and easy to use in multiple projects with minimal effort.

-Dustin T Waling

Will do thank you!