reloop.sh Domain Error
Why you cannot send from the reloop.sh domain via the public API.
Why you cannot send from the reloop.sh domain via the public send API.
Overview
reloop.sh (or your deployment's ONBOARDING_TEST_DOMAIN) is a Reloop-owned onboarding test domain. It is reserved for the onboarding Send email button — not for arbitrary customer domain setup.
If you call POST /api/mail/v1/send with a From address on that domain, Reloop returns an error directing you to use your own verified domain.
Common Causes
- Using
onboarding@reloop.sh(or similar) in a public/sendrequest - Trying to add
reloop.shas a customer domain in the dashboard - Expecting open sandbox sends to any recipient from the platform domain
What works instead
Onboarding test
After generating an API key, click Send test email to me. That path sends only to your account email from the platform domain.
Production sending
Add your domain in the dashboard, finish DNS verification, then send with a From address on that domain.
Contact support
If a legitimate platform test fails, contact Reloop support with the error payload and approximate time.
Learn More
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