Horde Groupware — Classic Open-Source Collaboration Suite
General Information
Horde Groupware is one of the older names in the open-source collaboration world. It started in the early 2000s as part of the Horde PHP framework and grew into a full suite with mail, calendars, tasks, and notes. For a long time it was the default groupware stack in many universities and mid-size companies that needed something free and customizable.
It doesn’t try to look like a shiny SaaS product — the interface feels traditional — but admins still value it for stability and the fact that it can be …
How It Works
Horde Groupware is a PHP web application that runs on top of Apache/Nginx with a database backend (MySQL, PostgreSQL). It connects to an existing IMAP/SMTP server for email and adds groupware modules on top: shared calendars, tasks, notes, and address books.
Users access everything from the browser. Sync to mobile and desktop apps is possible through CalDAV, CardDAV, and ActiveSync. Admins manage accounts through LDAP/AD integration or local user management. Because it’s modular, you can enabl…
Functions
Feature | In practice
—|—
Web interface | Browser access to mail, calendars, tasks, notes, contacts
Mail integration | Uses existing IMAP/SMTP servers
Calendars & contacts | Shared scheduling, CalDAV/CardDAV/ActiveSync support
Tasks & notes | Simple task lists and personal notes
Directory support | LDAP/AD integration for authentication
Modular design | Add-on modules from the Horde framework
Security | TLS/SSL sessions, role-based access
Platforms | Runs on Linux servers with Apache/Nginx + PHP
Licensing | Open source (GPL)
Installation Guide
1. Deploy a Linux server with Apache/Nginx, PHP, and MySQL/PostgreSQL.
2. Download Horde Groupware from the project repository or distribution packages.
3. Unpack and configure config/registry.php and database settings.
4. Connect it to your IMAP/SMTP backend.
5. Add CalDAV/CardDAV sync if mobile integration is required.
6. Create users locally or bind to LDAP/AD.
7. Test with a few accounts before moving to production.
Everyday Use
– Universities ran Horde for years to give students webmail and shared calendars.
– NGOs and small organizations adopted it for a free alternative to commercial suites.
– IT teams use it as a quick internal portal where staff can check mail, add events, and share contacts.
It’s not fancy, but it’s dependable. Users get the basics: mail, calendar invites, to-do lists. Admins get something that works on standard Linux stacks without licensing headaches.
Limitations
The UI feels dated compared to modern SaaS platforms. Collaboration features are basic — no built-in chat or video. Scaling to very large deployments can be complex, and documentation sometimes assumes knowledge of the broader Horde framework. Still, for small to mid-size environments, it’s functional and stable.
Comparison
Tool | Platforms | Strengths | Best Fit
—|—|—|—
Horde Groupware | Linux/PHP | Open-source, modular, long history | SMBs, NGOs, education
EGroupware | Linux/PHP | Similar feature set, lighter UI | Small teams, non-profits
Zimbra OSE | Multi-platform | Mature groupware, larger community | Schools, SMBs, mixed environments
Nextcloud + apps | Linux | File-first approach, extendable with apps | Teams focused on document work
Microsoft 365 | Multi-platform | Enterprise-grade, full collaboration | Large corporations
Notes from the Field
Admins who deployed Horde often mention that once it’s running, it just keeps running. Updates can be a bit manual, but the system itself is resilient. Many teams paired Horde with Postfix/Dovecot as the backend — the classic open-source mail stack. The common advice: don’t oversell it; Horde won’t replace Google Workspace, but it will cover the basics well.