Technical guide for Hovixa users on optimizing Apache SpamAssassin in cPanel. Learn to adjust spam thresholds, configure auto-delete settings, and manage whitelist/blacklist rules.

Spam Filters (SpamAssassin): Threshold Tuning and Custom Rules

Hovixa uses Apache SpamAssassin to protect your mailboxes from unsolicited bulk email. SpamAssassin performs a series of heuristic tests on incoming mail headers and body content to assign a "Spam Score." This guide details how to calibrate these settings to minimize false positives while maximizing filtering efficiency.

1. Understanding the Spam Threshold Score

Every incoming email is scanned and assigned a numerical value. The higher the score, the more likely the message is spam.

• 1 (Aggressive): Very strict. High probability of flagging legitimate newsletters or automated notifications.
• 5 (Default): Balanced setting suitable for most professional environments.
• 10 (Passive): Only the most obvious, poorly-constructed spam will be caught.

Adjusting the Score:

1. Log in to cpanel.hovixa.com.
2. Navigate to the Email section and click Spam Filters.
3. Locate the Process New Emails and Mark them as Spam section.
4. Click Spam Threshold Score.
5. Select a value from the dropdown. Technical Tip: If you are still receiving spam at "5", try "4". Never go straight to "1".

2. Auto-Delete vs. Spam Box

You have two primary options for handling messages that exceed your threshold:

1. Move to Spam Box: The message is delivered to a folder named Spam. You can review these via Webmail or IMAP. This is the safest setting to prevent data loss.
2. Auto-Delete: Any message exceeding the Auto-Delete Threshold Score is permanently purged. Warning: Use this only for extremely high scores (e.g., 8+) to ensure legitimate mail isn't accidentally destroyed.

3. Whitelisting and Blacklisting (Custom Rules)

Manual overrides take precedence over the heuristic scanner. If a specific sender is always blocked or always getting through, use the Additional Configurations.

Whitelisting (Trusting Senders):

1. Click Show Additional Configurations under Spam Filters.
2. Click Edit Spam Whitelist Settings.
3. Click + Add A New "whitelist_from" Item.
4. Use wildcards for entire domains: *@trustedpartner.com or specific addresses: [email protected].

Blacklisting (Blocking Senders):

1. Click Edit Spam Blacklist Settings.
2. Add entries using the same format: *@spamsite.net.
3. Click Update Blacklist.

4. Advanced: Calculated Header Inspection

When SpamAssassin marks an email, it modifies the email headers. You can view these headers in your mail client to understand why a message was flagged:

• X-Spam-Status: Shows the total score and the specific tests failed (e.g., BAYES_50, HTML_MESSAGE).
• X-Spam-Level: A visual representation of the score using asterisks (****).

Summary of Implementation

For optimal results, start with a threshold of 5 and the Spam Box enabled. Review your spam folder weekly. If you find no false positives after 14 days, you may consider lowering the threshold to 4 or enabling Auto-Delete for scores above 10.