> ## Documentation Index
> Fetch the complete documentation index at: /docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Why Emails Land in Spam and How to Fix Inbox Placement

> Learn the most common reasons emails end up in the spam folder and the steps you can take with turboSMTP to improve inbox placement and sender reputation.

A message accepted by turboSMTP or a receiving server can still land in spam. Review authentication, recipient consent, list quality, and mailbox-provider responses. No provider can guarantee inbox placement.

## Check the delivery evidence

Find the message in **Analytics** and read its status and reason. Inspect the received message's `Authentication-Results` header for SPF, DKIM, and DMARC outcomes. For bounces and complaints, review **Suppressions** and its **Type** column.

## Fix 1: Configure email authentication

* **SPF** authorizes sending servers for the envelope sender domain.
* **DKIM** signs message content and headers so receivers can verify the signing domain.
* **DMARC** checks alignment with the visible From domain and publishes your failure-handling policy.

Use the exact DNS values provided for your domain in the dashboard. Merge SPF mechanisms into one existing SPF record. See [Email Authentication](/docs/deliverability/spf-dkim-dmarc.md), including subdomain setup and the dashboard verification step.

The [DNS analyzer](https://serversmtp.com/spf-dkim-dmarc-dns-gdpr-analysis) can help inspect records. Confirm the result in DNS and received message headers; an analyzer result does not establish legal compliance or guarantee delivery.

## Fix 2: Clean your email list

Remove invalid addresses, duplicates, and recipients who have opted out or complained. Review inactive subscriptions before sending again. Use [Email Validation](/docs/account/email-validation.md) as one check; validation cannot establish consent or guarantee that a mailbox will accept future messages.

## Fix 3: Provide an unsubscribe path

For subscription mail, provide a clear unsubscribe link and process opt-outs promptly. Configure turboSMTP's unsubscribe element under **Settings → Email elements → Unsubscribe link** when appropriate for your messages. Keep application subscription preferences synchronized with **Suppressions**.

## Fix 4: Review tracking and content

Use accurate subjects, recognizable sender details, working links, and a useful text alternative to HTML. Avoid unexpected volume changes and send content recipients requested.

If you use open and click tracking, review your tracking domain. A [custom tracking domain](/docs/deliverability/custom-tracking-domain.md) uses a subdomain you control; it does not by itself guarantee better inbox placement. Availability depends on your plan: Free has a 30-day demo, Basic lists two custom tracking domains, and Pro lists unlimited domains. See [pricing](https://serversmtp.com/pricing/).

## Fix 5: Verify your sender domain

An unverified domain can use turboSMTP's re-enveloped sender mode. The authenticated envelope or signing domain may then differ from your visible From domain, which can affect DMARC alignment or cause a mail client to show an additional sender label.

Publish the dashboard's SPF and DKIM records, complete verification, and check the domain authentication mode. Inspect a received message to confirm alignment. The appearance of an "on behalf of" label depends on the mail client and message headers.

## Fix 6: Investigate Yahoo and AOL complaints

Read the actual deferral or rejection reason in **Analytics** before assuming the cause. A complaint feedback loop provides visibility into complaints; enrollment does not remove a block or erase the effect of complaints on reputation.

Yahoo's current [Complaint Feedback Loop](https://senders.yahooinc.com/complaint-feedback-loop/) uses Sender Hub and DKIM-domain enrollment. Its [FAQ](https://senders.yahooinc.com/faqs/) says older form registrations must be replaced by Sender Hub enrollment.

**1. Check provider enrollment**

Ask turboSMTP support whether your sending DKIM domain is already enrolled and how complaint processing is configured for your account.

**2. Enroll if needed**

Create a Yahoo Sender Hub profile, add and verify your DKIM signing domain, then enroll it in the Complaint Feedback Loop. Use a reporting address you control, or coordinate the reporting destination with turboSMTP support.

**3. Act on complaints**

Stop sending to recipients who complain. Review **Suppressions** for **Spam** entries and preserve opt-outs in your own application.

> [!NOTE]
>
> Yahoo guidance checked on 27 October 2026. For continued delivery problems, contact [support](https://serversmtp.com/contact-us/) with message IDs, timestamps, and redacted server responses.


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