Audience
Anyone looking for a powerful open source mail server
About Courier
The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, webmail, and mailing list services within a single, consistent, framework. Individual components can be enabled or disabled at will. The Courier mail server now implements basic web-based calendaring and scheduling services integrated in the webmail module. Advanced groupware calendaring services will follow soon.
The Courier mail server's source code should compile on most POSIX-based operating systems based on Linux, and BSD-derived kernels. The Courier mail server should also compile on Solaris and AIX, with some help from Sun's or IBM's freeware add-on tools for their respective operating systems.
The Courier mail server evolved out of several related projects, that merged together (more on that later). The Courier mail server implements SMTP extensions for mailing list management.
Other Popular Alternatives & Related Software
Mailu
Mailu is a simple yet full-featured mail server as a set of Docker images. It is free software (both as in free beer & as in free speech), open to suggestions and external contributions. The project aims at providing people with an easily setup, easily maintained and full-featured mail server while not shipping proprietary software nor unrelated features often found in popular groupware.
Main features include:
Standard email server, IMAP and IMAP+, SMTP and Submission with autoconfiguration profiles for clients
Advanced email features, aliases, domain aliases, custom routing
Web access, multiple Webmails and administration interface
User features, aliases, auto-reply, auto-forward, fetched accounts
Admin features, global admins, announcements, per-domain delegation, quotas
Security, enforced TLS, DANE, MTA-STS, Letsencrypt!, outgoing DKIM, anti-virus scanner, Snuffleupagus, block malicious attachments
Antispam, auto-learn, greylisting, DMARC& SPF, anti-spoofing
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Haraka
Haraka can serve thousands of concurrent connections and deliver thousands of messages per second. Haraka and plugins are written in asynchronous JS and are very fast. Haraka has very good spam protection (see plugins) and works well as a filtering MTA. It also works well as an MSA running on port 587 with auth and dkim_sign plugins enabled. Haraka makes no attempt to be a mail store (like an exchange or postfix/exim/qmail), an LDA, or an IMAP server (like Dovecot or courier). Haraka is typically used with such systems. Haraka has a scalable outbound mail delivery engine built in. Mail marked as relaying (such as via an auth plugin) is automatically queued for outbound delivery. Haraka's plugin architecture provides an easily extensible MTA that complements traditional MTAs that excel at managing mail stores but do not have sufficient filtering.
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Kopano
We provide you with your digitally sovereign solution to keep track of your e-mails and calendars, to organize yourself with tasks or to stay in contact with team colleagues via video meeting. Kopano Groupware is an e-mail and calendaring solution, which can be operated digitally sovereign. Its functionality is comparable to that of Microsoft Outlook and Exchange. Kopano Groupware installations can be operated with more than 100,000 users. Kopano Groupware is an e-mail and calendar server that provides users with their daily communication and organizational data on all devices and connects teams. Data can be jointly edited in public folders or shared with others from your own inbox.
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Mail-in-a-Box
Mail-in-a-Box lets you become your own mail service provider in a few easy steps. It’s sort of like making your own gmail, but one you control from top to bottom.
Technically, Mail-in-a-Box turns a fresh cloud computer into a working mail server. But you don’t need to be a technology expert to set it up.
Each Mail-in-a-Box provides webmail and an IMAP/SMTP server for use with mobile devices and desktop mail software. It also includes contacts and calendar synchronization.
The box also includes other standard mail functionality like spam protection (spam filtering and greylisting), mail filter rules, email client autoconfiguration, and automated backups to Amazon S3 and other services.
The box also includes automatic DNS configuration when you let it become your nameserver so that it can set important DNS records for mail deliverability and security including SPF, DKIM, DMARC, and MTA-STS. When enabled, DNSSEC (with DANE TLSA) provides a higher level of protection.
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Pricing
Starting Price:
Free
Pricing Details:
Open source
Free Version:
Free Version available.
Integrations
Company Information
Double Precision, Inc.
Founded: 1995
France
www.courier-mta.org
Videos and Screen Captures
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Product Details
Platforms Supported
Linux
Training
Documentation
Courier Frequently Asked Questions
Q: What kinds of users and organization types does Courier work with?
Courier works with these users and organization types: Mid Size Business, Small Business, Enterprise, Freelance, Nonprofit, Government, and Startup.
Q: What languages does Courier support in their product?
Courier supports these languages: English.
Q: What other applications or services does Courier integrate with?
Courier integrates with: Aid4Mail, Debian, and LDAP.
Q: What type of training does Courier provide?
Courier provides training in the form of documentation.
Q: How much does Courier cost?
Pricing for Courier starts at Free.
