> Source: [sk184868](https://support.checkpoint.com/results/sk/sk184868)

# sk184868 - SMTP 554 "Spam email" errors for legitimate mail after increasing Anti-Spam protection on Check Point MTA

| Property | Value |
|----------|-------|
| Solution ID | sk184868 |
| Date Created | 2026-04-08 |
| Last Modified | 2026-04-12 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82 |
| OS | Gaia |
| Platform | 6000 |

## Symptoms

- * The Check Point MTA rejects legitimate inbound emails.

* External senders receive an SMTP error similar to: "554 Spam email. Email Session ID: {69AAC277-2-533AE0D4-E4ABDEDB}"

* The Anti-Spam protection level on the Security Gateway was changed from Medium to High.

* After changing from Medium to High, bulk or notification-type emails (newsletters, system notifications, marketing mail) that were previously delivered are rejected.

* When the Anti-Spam protection level is changed back to Medium, the same emails are accepted and delivered.

## Cause

The MTA Security Gateway uses the Cyren content filter engine to classify email messages.

When the Anti?Spam protection level is set to **High** , the engine classifies more messages as **spam** or **suspected spam (Bulk)**.

If the configured action is **Reject**, the MTA rejects these messages with an SMTP 554 error to the sender.

## Solution

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