Summary
Multiple production apps are failing to send transactional emails via the built-in Retool Email resource, returning the error "421 Domain retool-email.com is not allowed to send: Disabled for sending spam."
AI Response
This matches a known, active platform incident: Retool's status page confirms an unresolved incident titled "retool-email unavailable" (opened Jul 23, 2026 22:22 UTC), with the Email Server component in a Major Outage state due to the retool-email.com domain being disabled for spam. Per that incident note, official Retool emails like user invites and password resets are unaffected — only the shared sending domain used by the Email resource is impacted. Since this is a shared-domain issue on Retool's side, the fix is being handled by Retool, and subscribing to the incident is the best way to track resolution. As an interim mitigation for critical transactional emails, routing sends through your own email provider (for example, a configured SMTP resource or an external email API rather than the internal Retool Email resource) avoids dependence on the affected retool-email.com domain.
Sources
https://status.retool.com
Confirms the active 'retool-email unavailable' incident and that the retool-email.com sending domain was disabled for spam, directly matching the reported error.
A recent thread discussing alternatives to the internal Retool Email and SMTP resources, useful as an interim workaround for critical transactional emails.
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