Microsoft Outlook Add attachment
Add a file, item, or link attachment to a message. This operation limits the size of the attachment to under 3 MB. For larger files (3 MB to 150 MB), use the upload session endpoint.
Add a file, item, or link attachment to a message. This operation limits the size of the attachment to under 3 MB. For larger files (3 MB to 150 MB), use the upload session endpoint.