What We Fixed
Sending an email from a contact record through a connected Microsoft Outlook account failed with a “Failed” status whenever a recipient field (To, Cc, or Bcc) held more than one comma-separated address. The whole address list was being passed to Microsoft as a single, unrecognized recipient, so Microsoft rejected the message — even though the inbox was connected and syncing normally.
Multiple comma-separated recipients are now split into individual addresses before sending, so these emails deliver as expected.
We also hardened the Outlook send path: a stale access token is now refreshed and the send retried automatically (matching how inbox sync already behaves), and recipient-related failures now show a clear, actionable message instead of a generic error.