5

I am trying to send an email as a reply to a previous thread using SendGrid v3 APIs. But it always shows as a new email thread in Outlook. I am using "Message-ID", "In-Reply-To" and "References" fields but it always fails to show under single thread. I am referring this thread here to set the headers.

SendGrid document doesn't specify if v3 supports replying to previous thread or not. Any way to achieve email thread conversation is appreciated.

Prasad Bhokare
  • 349
  • 1
  • 2
  • 12

1 Answers1

6

OKAY. I figured out the key here. I was missing "<>"angled brackets and looks like SendGrid takes it very seriously. So this is how headers section should look like.

"headers": {
    "Message-ID": "<11a7efc0-8f79-4569-a038-939b7b2b303@server.com>",
    "In-Reply-To": "<11a7efc0-8f79-4569-a038-939b7b2b301@server.com>",
    "References": "<11a7efc0-8f79-4569-a038-939b7b2b301@server.com>"
}

Checkout the angled brackets surrounding header values.

Prasad Bhokare
  • 349
  • 1
  • 2
  • 12