When creating a marketing email with a From address that uses an unauthenticated domain, HubSpot automatically rewrites the From and Reply-To addresses to a HubSpot-managed domain (e.g., user=company.com@hs-send.com ). This rewrite happens silently at send time with no warning in the marketing email editor.
This creates significant issues for senders:
Recipients see an unfamiliar sender address that looks like spam or phishing
Replies may not be delivered because some email clients reply to the visible From address instead of the Reply-To header, and @HS-send.com domains do not accept incoming mail
Brand trust is damaged when important campaigns appear to come from a suspicious address
No opportunity to fix the issue before sending, leading to embarrassing situations with customers
Current Behavior:
HubSpot added warnings for unauthenticated domains in Inbox/Help Desk workflows and during new email account creation (February 2024 changelog). However, no warning appears in the marketing email editor when scheduling or sending an email that will have its From address rewritten.
Requested Feature:
Display a prominent warning banner in the marketing email editor (on the Send/Schedule screen) when:
The selected From address uses a domain that is not connected/authenticated as an email sending domain
The email will be sent with a rewritten @HS-send.com address
The warning should:
Clearly explain that the From/Reply-To addresses will be rewritten to user=domain.com@hs-send.com
Warn that recipients may not be able to reply successfully
Link directly to the domain authentication setup page (Settings → Content → Domains & URLs)
Require acknowledgment before allowing the user to proceed with Send/Schedule
Business Impact:
Without this warning, users unknowingly send critical campaigns with broken sender addresses, resulting in:
Lost replies and customer communication failures
Damage to brand reputation and email deliverability
Wasted marketing spend on campaigns that appear untrustworthy
Support burden when users discover the issue after the fact
Use Case:
A marketing manager schedules an important product launch campaign to 10,000 customers using team@company.com as the From address. They have not yet authenticated company.com as an email sending domain. The campaign sends successfully, but recipients see emails from team=company.com@bf06.hs-send.com . Many customers:
Mark the email as spam due to the suspicious sender
Try to reply but their messages bounce because @HS-send.com doesn't accept incoming mail
Contact support asking why they received a "fake" email
A simple warning before send would have prevented all of these issues by prompting the user to authenticate their domain first.
Expected Behavior:
Similar to how HubSpot warns users about:
Unauthenticated domains in Inbox/Help Desk (already implemented)
Missing unsubscribe links in marketing emails
Emails with no subject line
Workflows that will affect large numbers of records
This warning should appear before irreversible actions (sending/scheduling) to give users the chance to fix configuration issues.
Workaround:
Currently, the only way to discover this behavior is:
Send a test email to a personal inbox and inspect the headers
Read the knowledge base documentation (which many users don't do before their first send)
Experience the problem after an important campaign has already been sent
None of these are acceptable for preventing a serious deliverability and brand trust issue.
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