Free Outlook Plugin, which synchronizes events, tasks and contacts between Outlook and Google, SOGo, Nextcloud, 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
- 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, mailbox.org
- 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
- Support for WebDAV Collection Sync (RFC 6578)
- 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/
- create DAV server calendars/addressbooks with MKCOL
- Map Outlook formatted RTFBody to html description via X-ALT-DESC attribute
- Support for RFC7986 per-event color handling, mapping of Outlook category color to COLOR attribute
Very good tool... tested during one month without any problem Deserves a donation Thank you
very good tool
Works great syncing Outlook contacts, calendars and tasks with NextCloud. My setup : Windows 10 64 bits, Microsoft Office 32 bits, NextCloud 12. I was previously using gSyncit from Fieldston Software for the same purpose, but this is both faster to sync and easier to set up in the first place. In particular, the auto-discovery functionality is nifty, whereby the Outlook plugin identifies on the NextCloud server all the calendars and address books you might want to interact with. I also like the ability to export and re-import settings : useful when you need to configure the same Outlook profile on several different machines, or when you need to reinstall your profile. Many thanks to the developers for making this open-source and free of charge.
This tool is very usefull for team calendars without using Exchange. Runs very stable. High update rate is accepted by my colleages, that's important. Good work, many thanks!
Works better than most of commercial tools. I'm using it to sync my Outlook 2007 calendars, contacts and tasks on a Synology.