Confirm the intended domain and the scope of the DirectAdmin filters for your account. Review legitimate correspondence before blocking the whole domain. A forged sender domain can appear in spam, so inspect examples rather than trusting a display name.

1. Open E-mail Manager > SPAM Filters for the correct domain context.
2. Choose the Domain match type.
3. Enter only the sender domain, such as example.com, without a protocol, path or unnecessary www prefix.
4. Review the action applied to matches and add the rule. Use a reviewable destination during evaluation when your installation provides one.
5. Monitor incoming mail and confirm the intended scope, including how the implementation handles subdomains. Do not assume every matching rule treats parent and child domains identically.

Check that the unwanted source is filtered and that important business mail still arrives. Review filtered mail and any delivery complaints from users affected by the domain-wide rule.

If a legitimate sender is blocked, remove or narrow the rule and test again. Blocking a large public email provider can exclude many unrelated people, so prefer a precise sender rule or scored spam filtering where suitable. If spam forges changing domains, repeatedly expanding the block list may create more false positives without fixing the underlying pattern.

• Blocking a specific sender address with DirectAdmin email filters
• Filtering email by a subject or message keyword in DirectAdmin
• Removing an unwanted DirectAdmin email filter
• Enabling account spam filtering in DirectAdmin

• DirectAdmin Evolution: Email