Free Outlook Plugin, which synchronizes events, tasks and contacts between Outlook and Google, SOGo, Horde or any other CalDAV or CardDAV server. Supported Outlook versions are 2016, 2013, 2010 and 2007.
This project was initially developed as a master thesis project at the University of Applied Sciences Technikum Wien, Software Engineering Degree program. Outlook CalDav Synchronizer is Free and Open-Source Software (FOSS), still you can support the project by donating on Sourceforge or directly within the About dialog of our Plugin.
For collaboration with Nextcloud, see
Contact us for enterprise support at
Vote for us for March "Community Choice" Project of the Month! https://sourceforge.net/p/potm/discussion/vote/thread/22addff6/
- free and open-source software (FOSS), the only free Outlook CalDav plugin (AGPL license)
- tested CalDAV servers: SOGo, Google Calendar, Horde Kronolith, NextCloud, OwnCloud, SabreDAV, Synology NAS, GroupOffice, one.com, Yandex, OpenX-change, Posteo, Landmarks, Kolab, Zoho Calendar, GMX, Tine 2.0, Fruux, Mac OS X Server, iCloud, Mail.ru, Radicale, Cozy Cloud, Cyrus Imap 2.5
- modern WPF GUI
- Supporting OAuth2 for Google
- SSL/TLS support, support for self-signed certificates
- Manual proxy configuration support for NTLM or basic auth proxies
- Autodiscovery of calendars and adressbooks via well-known redirects or DNS SRV/TXT lookups
- configurable sync range
- sync multiple calendars per profile
- sync reminders, categories, recurrences with exceptions, importance, transparency
- sync organizer and attendees and own response status
- task support
- CardDAV support to sync contacts (distribution lists planned)
- Google native Contacts API support with mapping of Google contact groups to Outlook categories.
- Google Tasklists support (sync via Google Task Api with Outlook task folders)
- sync contact pictures, categories, notes and x509 certificates
- manual or time-triggered sync
- change-triggered sync
- sync triggered by Outlook Send/Receive
- Category Filtering (sync CalDAV calendar to Outlook categories)
- map CalDAV server colors to Outlook category colors
- show reports of last sync runs and status
- configurable system Tray Icon with notifications
- bulk creation of multiple profiles
- Use server settings from Outlook IMAP/POP3 account profile
- Map Windows to standard IANA/Olson timezones
- Configurable mapping of Outlook custom properties
- Backport for WinXP and .Net 4.0 available at https://sourceforge.net/projects/outlookcaldavsynchronizerxp/
A really great tool! Works like a charm with Outlook 2010 and ownCloud, absolutely stable. Thanks a lot!
Thank you for the realization of this tool which was only missing for years. Perfect synchronization with owncloud / nextcloud for contacts, calendars, tasks. I tested it on large address books and multiple calendars with Outlook 2010 and 2016. Options really well thought out like using the mail account username and password for sync. Microsoft Outlook does not fully support IMAP, nor does it support either Caldav or Carddav. Is it really a mail client? I think Outlook is a fine software however that the firm should not close so much because openness is always the best strategy and you have made the proof of it. Thank you ++. I can help with translation (french) if needed. pshadoko@sourceforge
Epic Stuff! Working perfectly with Owncloud 9.0.2 for the last 2 months. Message to the Devs: I searched in many places for ages for "Carddav Outlook" since contacts was my primary problem, and only found assorted buggy crap or expensive proprietary solutions. It wasn't until I started searching on "Caldav Outlook" that I came across this. Maybe change the name of the Plugin to include the word 'carddav' so it will be found more easily? Anyway...keep it up. Tks :)
Works very well. I had trouble with another program from SourceForge, while this one does the job perfectly. I'm using it to synchronize my private Outlook calendar to my phone with a Google Calendar as intermediate.