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Block senders and IP addresses

In Allow & block, add a sender to Blacklisted senders or an IP address to Denied connection IPs, and SpamDuster rejects their mail every time. Whitelisted IPs on the same page lets a trusted sending server bypass filtering.

What the Allow & block lists do

The lists on Allow & block act before any other check:

List Group Effect
Whitelisted IPs Allowed Mail from these IP addresses bypasses filtering.
Blacklisted senders Blocked Mail from these senders is always rejected.
Denied connection IPs Blocked Connections from these IP addresses are always refused.

Block a sender

  1. In the console, open Allow & block.
  2. Under Blacklisted senders, type the address, for example [email protected], or the domain, for example promo.example, in Add sender….
  3. Select +.

The Allow & block page with the Blacklisted senders list outlined

Block an IP address

  1. In Allow & block, type the IP address in Add ip… under Denied connection IPs.
  2. Select +.

Remove an entry

Select the × (Remove) next to the entry. Only entries you added yourself can be removed. Entries that came with the filter are hidden by default; select Show … built-in entries under a list to see them.

Allowing a single sender instead

To let mail from one sender skip the spam checks while still scanning it for malware, use Allowed senders rather than Whitelisted IPs. See Allow a sender.

Updated 2026-10-26Need help? Open a ticket in the billing portal.