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— Troubleshooting

Custom email domain DKIM is failing

A red DKIM badge in Settings → Email → Custom domain usually traces to one of four causes. Walk the branches in order — most failures resolve in under thirty minutes.

Last updated · May 6, 2026 Read time · 3 min Author ·

DNS hasn't propagated yet

DNS records take five to thirty minutes to reach Postmark's resolvers, and longer on providers with high TTL defaults. If the records were added in the last hour, click Verify again after a short wait. Confirm the records are live with dig TXT <dkim-host> from a terminal — if your terminal can't see them, neither can Postmark.

Screenshot needed

Alva admin Settings → Email → Custom domain panel. DKIM row showing a red Failed badge, Return-Path row showing Pending. Verify button visible. Highlight the DKIM red badge with a red box. No real domain visible — use example.com.

The verification status panel with a failed DKIM badge.

You used DKIMHost / DKIMTextValue instead of DKIMPendingHost / DKIMPendingTextValue

Postmark's domain detail page exposes both DKIMHost/DKIMTextValue and DKIMPendingHost/DKIMPendingTextValue. During onboarding the non-pending fields are empty — only the Pending values carry the real DKIM record. Alva pre-fills the Pending values automatically; if you copied directly from the Postmark dashboard instead, you may have grabbed the empty pair. Re-copy from the Alva admin and update the TXT record value at your DNS provider.

Screenshot needed

Postmark dashboard, Sending → Domains → domain detail page. Show the DNS section with both DKIMHost (empty) and DKIMPendingHost (populated) fields visible. Highlight the DKIMPendingHost row with a red box and an arrow labelled "use this one". Crop browser chrome.

Postmark's domain detail page — only the Pending fields hold valid records during onboarding.

Postmark error 512: Domain already exists

Postmark returns error 512 when the domain is registered against another Postmark account — usually a previous Alva install, an unrelated Postmark customer, or a different Alva shop in the same organisation. Two paths forward: delete the domain from Alva (which removes it from Postmark) and re-add it, or contact support if it's held by a separate account.

The shop downgraded mid-setup

Alva resolves the sender on every send and re-checks the plan tier each time. If the shop dropped to the Free plan after DKIM was verified, delivery emails revert to the default digitaldownloads@alvaapps.com sender — DKIM stays green in the panel but stops being used. Custom sender domains require Basic, Pro, or Enterprise. Upgrade from Shopify billing and the next email sends from your branded address.

Wrong record type — TXT vs CNAME

The DKIM record is a TXT record. The Return-Path record is a CNAME at pm-bounces.<your-domain> pointing to pm.mtasv.net. DNS providers default new records to A or CNAME — selecting CNAME for the DKIM row produces a permanent failure no amount of waiting will fix. Delete the misfiled record, add a TXT record with the same host and value, and re-verify.

See also

Email delivery

Set up a custom email domain (DKIM walkthrough)

Register a sender domain with Postmark, add the DNS records, and verify end-to-end.

 Troubleshooting

Why your customer didn't receive their download email

Walk the five most common causes: fraud holds, suppressions, spam filters, and DKIM failures.

 Email delivery

Customise your delivery email

Edit the subject line, body, and branding so emails arrive looking like they came from your store.

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Last updated 2026-05-06