Best Kundenserver Alternatives & Competitors in 2025

SpamHero is a professional spam filtering accuracy while lowering the cost to domain and business owners.

SpamExperts applies its proprietary smart technologies to eliminate spam, virus and malware mail before it reaches your network.

The #1 email warming service to improve your deliverability by generating realistic and meaningful engagement to your emails. Easy-to-use solution to help you land in the main inbox instead of the spam folder.

Visit website paid $19.5 / Monthly (Pro)

The outbound email filtering prevents spam from being unknowingly sent out of your network through a compromised account or script.

Protect mail server against spam, viruses and malware with Proxmox Mail Gateway security for businesses, government, education and non-profit organizations.

Reduce costs with Mimecast's cloud archive to move to the cloud with a single, secure archive for email, files and other content.

MegaNameServers is committed to providing a professionally managed outsourced email abuse solution.

Use this program to "Unspam" your mailbox(es).

Open Source

Comprehensive Email Protection. 99.99% Spam Detection. Blocks phishing, viruses, malware and other email threats.

Open Source Free Trial $0.81 / Monthly (Per User)

Datatune's hosted antispam solution is a cloud-based email security tool.

Spam Reader is a free anti-spam add-on for Microsoft Outlook.

Rspamd is an advanced spam filtering system that allows evaluation of messages by a number of rules...

MailScanner is a open source email security system design for Linux-based email gateways.

CanIt for small and medium automatically protects email from spam.