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SpamDuster On-Premise Outbound

SpamDuster On-Premise Outbound is not available yet. It will be an appliance that filters the mail your servers send, so a compromised account or a hijacked script cannot turn your network into a spam source and get your IP addresses blocklisted.

Coming soon: this is not available yet.

Availability

SpamDuster On-Premise Outbound is coming soon and cannot be ordered yet. SpamDuster Cloud filters incoming mail only.

What On-Premise Outbound will do

On-Premise Outbound will filter the mail your servers send, before it leaves your network:

  • every outgoing message checked for spam, viruses and phishing;
  • spam sent through a stolen password or an exploited script caught and held, instead of reaching thousands of recipients;
  • your sending reputation protected, helping to keep your IP addresses off blocklists.

How it will fit in

Your mail servers will relay their outgoing mail through the appliance as a smart host. Nothing changes for your users.

Where it will run

On-Premise Outbound will run on VMware ESXi, Microsoft Hyper-V, KVM or Proxmox, or a physical server (BIOS or UEFI), on your own hardware or virtualization platform. It will not be offered on AWS, Google Cloud or Azure marketplaces.

How it will be licensed

On-Premise Outbound will be licensed per mail server:

  • Mail-server licences: one for each mail server the appliance protects, 5 mail servers or more. Each licensed mail server that runs a supported hosting control panel (cPanel & WHM, Plesk on Linux or Windows, and DirectAdmin) includes unlimited domains and mailboxes.
  • Domain packs: for domains added by hand or through the billing API, without a control panel. Packs combine in any mix and need no server licence.
  • Inbound and outbound are separate appliances, licensed separately.

You will activate each appliance by entering the appliance ID and activation code from your welcome email on the appliance console. The appliance will need an internet connection to activate its licence and to receive filter and security updates.

What On-Premise Outbound will cost

A mail-server licence will cost $720 a year or $72 a month per mail server, for 5 mail servers or more. Paying yearly costs the same as 10 months.

Outbound domain packs

Domains Addresses Yearly Monthly
25 250 $240 $24 (with a server licence)
50 500 $400 $40 (with a server licence)
100 1,000 $700 $70 (with a server licence)
250 2,500 $1,500 $150
500 5,000 $2,500 $250
1,000 10,000 $4,000 $400

The addresses a pack covers are the addresses that sent mail in the last 30 days. A pack under $100 a month can be paid monthly only alongside an active server licence; bought on its own, it is paid yearly.

If you go over your On-Premise Outbound licence

Your mail will never stop: it will keep being filtered and sent. A mail server beyond your licences will not connect, and a domain beyond your packs will be refused when it is added, until you add a licence or a pack. If more addresses send mail than your packs cover, you will get an alert.

If a licence lapses

If a licence lapses, mail keeps being filtered and delivered for 14 days while the management console, reporting and additional detection engines pause; after that the appliance holds new mail with a temporary error, so sending servers queue it and retry, and delivery resumes as soon as the licence is renewed. Sending servers give up after about 5 days, so renew promptly.

Updated 2026-10-28Need help? Open a ticket in the billing portal.