Password recovery emails failing with custom SMTP (Resend)

[Temujin-67]

Hi everyone,

I’m running into an issue with password recovery emails in Supabase and would appreciate some clarification.

I’ve configured custom SMTP using Resend, and password reset requests are consistently failing.

What I’m seeing:

Calling POST /auth/v1/recover returns HTTP 500

Error response:

error_code: unexpected_failure
msg: Error sending recovery email

What I’ve already checked:

Requests reach the correct endpoint and include valid headers

Custom SMTP is enabled with:

Host: smtp.resend.com

Port: 465

TLS: implicit SSL

TLS connectivity to Resend is working

The same SMTP credentials successfully send emails outside Supabase

One important detail:
The sender domain is not fully verified yet (SPF/DKIM records are still pending in Resend).

Is it expected that password recovery emails fail with this generic 500 error until the sender domain is fully verified when using custom SMTP?
If so, is there a recommended way to surface a clearer error or confirm this behavior via logs?

Thank you.

[GaryAustin1]

Look in the auth logs for details on the error (if any) Resend is sending back.
Not sure why though it would be particular to password recovery versus any other type of auth email.