Outlook Plugin, which synchronizes events, tasks and contacts(beta) between Outlook and Google, SOGo, Horde or any other CalDAV or CardDAV server. Supported Outlook versions are 2016, 2013, 2010 and 2007.

https://sourceforge.net/projects/outlookcaldavsynchronizer/

Affero GNU Public License

• Gerhard Zehetbauer
• Alexander Nimmervoll

This project was initially developed as a master thesis project at the University of Applied Sciences Technikum Wien, Software Engineering Degree program

• SOGo
• Horde Kronolith
• OwnCloud
• SabreDAV
• Google Calendar
• Zimbra 8.5
• GroupOffice
• Synology NAS
• One.com
• DAViCal
• Baïkal
• Yandex
• OpenX-change

• open source AGPL, the only free Outlook CalDav plugin
• two-way-sync
• SSL/TLS support, support for self-signed certificates
• Autodiscovery of calendars and addressbooks
• 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 (beta)
• CardDAV support to sync contacts (beta)
• change-triggered-sync

• DDay.iCal
• Apache log4net
• Thought.vCard
• NodaTime

Download and extract the OutlookCalDavSynchronizer-<Version>.zip into the same folder and start setup.exe. If the installer is complaining about the missing Visual Studio 2010 Tools for Office Runtime, install it manually from Microsoft Download Link

• Delete profile cache, if outlook-folder or caldav-server-url is changed, ticket #117, prevents data loss and forces new inital sync in such cases
• Fix for linebreak issues of OpenX-change, merged from pull request #79, thx to bjoernbusch

• New features:
  • Support for proxy configuration in GUI to specify manual proxy settings and allow Basic Auth and NTLM proxies
• bug fixes:
  • Use ContactItemWrapper and reload Items to avoid a second sync with a changed modification time in Outlook, see ticket #111
  • Avoid sending meeting response if meeting is self organized
  • Avoid unnecessary connection tests during autodiscovery, fixes Google CardDAV autodiscovery

• New features:
  • Autodiscovery for CardDAV addressbooks
  • Change-triggered partial sync (Synchronize appointment items immediately after change in Outlook)
  • Support Yandex CalDAV server
  • Many improvements for CardDAV
  • Add OAuth Scope for Google CardDAV
• bug fixes:
  • Fix syncing contact notes with umlauts
  • Disable TimeRangeFiltering when contact folder is chosen
  • Ensure that FN of vcard is not empty, since it is a MUST attribute (bug #109)
  • Map AccessClassification of vcards
  • Ensure that vcard UID is not empty also in Updates
  • Skip addressbook collection itself when fetching vcards from Owncloud
  • Use existing UID for filename in PUT requests
  • Get ETAG via propfind if it is not returned in header to avoid Null Reference
  • Check also for Write privilege when detecting calendar access rights
  • Map other vcard telephonenumber types
  • Honor RevisionDate in vcard Updates if available (bug #111)
  • Fix InitialEventEntityMatcher if DTEnd is null (bug #110)
  • Filter only ContactItems in ContactRepository GetTable to avoid COM Exceptions, since we don't sync groups or distribution lists at the moment
  • Avoid exception in Autodiscovery DoubleClick EventHandler when clicking the header

• Fix regex in workaround for DDay.iCal timezone parsing, should fix bug #105 for syncing with Owncloud/Davdroid
• Rework of exdate generation to work around some strange Outlook Exception Collection missing elements, fixes Bug #91 and other recurrence exceptions with complex patterns

• Another fix for VTIMEZONE definition for Google, hopefully fixes US and Moscow timezone
• Add UID when vCard is created, according to the RFC UID is mandatory
• Another fix for recurrence exceptions and exdates for Bug #101
• Handle exceptions when updating outlook folders or during profile loading at startup

• Another DDay.iCal Workaround to fix VTIMEZONE generation for timezones wih changing DST rules like Moscow or Cairo
• bugfix: Use timezone ID for comparison, avoid exporting double VTIMEZONE definitons
• Options for not using keepalive and accepting invalid headers added

• Use StartTimeZone and EndTimeZone of events if different to system timezone
• Map server timezones to Windows Timezones and set time in StartTimeZone to fix recurring events which span DST shifts (fixes bug #94)
• Fix many cases of mapping recurrence exceptions and finding them over DST changes or if Outlook and Server are in different timezones
• Fix for bug #101, wrong exdate calculation
• Fix originalDate calculation of recurrence exceptions if they are on previous day in UTC
• Don't export historical timezone data before 1970

• Add mapping of IMAddress for contacts
• Add mapping of contact notes
• Fix vcard mapping for fax numbers and address type other
• Add doubleclick eventhandler for Autodiscovery
• Fixed TestConnection behavior, so that cancelling Autodiscovery works
• Add mapping of contact photos
• Mapping of FormattedName for contacts
• Add mapping for X509 certificates for contacts (e.g. S/MIME) to vCard KEY attribute
• Implement EmailAddress Mapping for Exchange contacts (type "EX")

• Initial CardDAV support to sync contacts (alpha)
• Refactoring of Autodiscovery
• Fix options and about buttons for Outlook 2007

• Add support for Outlook 2007, credits to PierreMarieBaty (pull request #67)
• Refactoring of Autodiscovery
• Refactoring of url validation and test settings
• Added option to automatically fix synchronization settings.
• Avoid ArgumentOutOfRangeException in attendee email substring

• Fix reminder timespan value

• Fix reminders for google
• Clarify test settings info for read-only resources and set Synchronization mode

• Add guard to prevent that a SynchronizationWorker is running multiple times.
• Fix priority mapping for tasks.
• Initial implementation of recurring tasks.

• Add support for Autodiscovery of CalDAV urls
• Workaround: Since DDay.iCal is not capable to parse events, which contain unsorted TimeZoneComponents, they must be sorted before parsing.

• Fixed bug in InitialEventEntityMatcher which caused a duplication of events, when a profile was deleted and recreated.
• Catch UriFormatExceptions in attendee and organizer Values from CalDav.
• Include response message in exception, if a protocol error occurs.

• Fixed HttpClient redirect issue, which affected Zimbra integration

• Added option to ignore new version and wait for next update.
• Added workaround for Group Office, which will tolerate empty VALARMs.
• Disable SynchronizeNowButton during synchronization.
• Disable TestConnectionButton while test is in progress.
• Add proper disposing for web messages.

• Support for Google OAuth
• Perform all web operations in the Background

-Fix TimeRange filter for events

• Add feature, which checks if a newer version is available (Ticket 61)

• Bugfix: Preserve UID when updating an Event.

• Make filtering for time range optional

• Implement app.config options for disabling SSL/TLS certificate validation and enabling/disabling SSL3/TLS12

• Use BYSETPOS also for other instances from Outlook fixes first/second/... weekday/weekend day in month

• Use BYSETPOS -1 to fix last (working)day monthly/yearly recurrences from Outlook
• Add UserAgent header to request. (needed by BAIKAL for example)

• Fix Bug: Mapping is wrong, when master event is not first event in CalDAV resource.
• Fix logging issue
• Fix recurrence from Outlook for last weekday in month

• Fetch Etag from server, if it is not included in an update response.
• Factor out CalDavWebClient from CalDavDataAccess.

• Dispose Folders in OptionDialog
• Call GarbageCollector after each synchronizer run to avoid issues with recurrence exceptions

• Fix some caldav timeout issues, properly dispose WebRequests

• Check if organizer address is empty to avoid COM Exception in GetMailUrl
• Fix exdate calculation for moved recurrence exceptions

• Catch 404 response for empty caldav repositories from Synology
• Some generic Refactoring

• Dispose Outlook-Folders after usage
• Some more recurrence exception fixes:
• If Outlook provides a Changed-Exception and a Deleted-Exception with the same OriginalDate the Deleted-Exception is discarded
• Prevent skipping of Appointment-exceptions while moving
• Swap handling of ExeptionDates and RecurrenceIDs
• Clarify logging error
• check if new exception is already present in target

• Fix timezone definition

• fix timezone issues for syncing from Outlook to CalDav for recurrent events
• Add local timezone info to new CalDav events
• Set start and end date in local timezone instead of utc for CalDav events
• fixes recurrent events that span over daylight saving time changes
• fix calculation of exdates for recurrence exceptions
• Fix date calculation for GetOccurence
• Honor BYSETPOS for monthly and yearly recurrence rules

• Improved validation of calendar url in options dialog

• Fixes for google

• Add SCHEDULE-AGENT=CLIENT for organizer to avoid sending invitations twice in SOGo, see ticket 45

• Add debug logging for caldav requests

• more fixes for exchange email addresses for attendees and better logging
• catch COM exception for not found recurrence exceptions

• more fixes for GetMailUrl
• Improve handling of WebExceptions

• fixes for GetMailUrl for Exchange and GAL
• fix WebException exceptions
• response header 'location' is allowed to contain a relative Uri

• fix interval for yearly recurrence rules

• add synchronization context if missing
• fix for task sync if start and due dates are equal

• swap default values for sync timespans in options dialog
• catch exceptions if PR_SMTP_ADDRESS property not available
• set meetingstatus to nonmeeting if only own organizer and no attendees are present

• Initial task sync support (alpha)
• Make caldav requests async, Outlook UI stays responsive during caldav get requests
• some recurrence fixes
• improve total progress handling

• Fixes for google

• Fix getting smtp address for exchange users

• Implement 301,302 redirects to support Zimbra
• Add validation for options

• Fix exception in initial mapping if event subject or summary is null

After installing the plugin, a new ribbon called 'Caldav Synchronizer' is added in Outlook with 3 menu items.

• Synchronize now
• Options
• About

Use the Options dialog to configure different synchronization profiles. Each profile is responsible for synchronizing one Outlook calendar or task folder with a remote folder of a CalDAV server.

• Add adds a new empty profile
• Delete deletes the current profile
• Copy copies the current profile to a new one

The following properties need to be set for a new profile:

• Profile name: An arbitrary name for the profile, which will be displayed at the associated tab.
• Server settings:
  • DAV Url: URL of the remote CalDAV or CardDAV server. You should use a HTTPS connection here for security reason! The Url must end with a / e.g. https://myserver.com/
  • If you only have a self signed certificate, add the self signed cert to the Local Computer Trusted Root Certification Authorities. You can import the cert by running the MMC as Administrator. If that fails, see section 'Debugging and more config options'
  • Username: Username to connect to the CalDAV server
  • Password: Password used for the connection. The password will be saved encrypted in the option config file.
  • Email address: email address used as remote identity for the CalDAV server, necessary to synchronize the organizer
• Outlook settings:
  • Outlook Folder: Outlook folder that should be used for synchronization
  • Synchronize changes immediately after change Trigger a partial synchronization run immediately after an item is created, changed or deleted in Outlook via the Inspector dialog, works only for Appointments at the moment!
• Sync settings:
  • Synchronization settings
    • Outlook -> CalDav (Replicate): syncronizes everything from outlook to caldav server (one way)
    • Outlook <- CalDav (Replicate): synchronizes everything from caldav server to outlook (one way)
    • Outlook -> CalDav (Merge): synchronizes everything from outlook to caldav server but don't change events created in caldav server
    • Outlook <- CalDav (Merge): synchronizes everything from caldav server to outlook but don't change events created in outlook
    • Outlook <-> CalDav: 2-way synchronization between Outlook and CalDav server with one of the following conflict resolution
  • Conflict resolution (only used in 2-way synchronization mode)
    • Outlook Wins: If an event is modified in Outlook and in CalDav server since last snyc, use the Outlook version. If an event is modified in Outlook and deleted in CalDav server since last snyc, also use the Outlook version. If an event is deleted in Outlook and modified in CalDav server, also delete it in CalDav server.
    • Server Wins: If an event is modified in Outlook and in CalDav server since last snyc, use the CalDav server version. If an event is modified in Outlook and deleted in CalDav server since last snyc, also delete it in Outlook. If an event is deleted in Outlook and modified in CalDav server, recreate it in Outlook.
    • Automatic: If event is modified in Outlook and in CalDav server since last snyc, use the last recent modified version. If an event is modified in Outlook and deleted in CalDav server since last snyc, delete it also in Outlook. If an event is deleted in Outlook and modified in CalDav server, also delete it in CalDav server
  • Synchronization interval (minutes): Choose the interval for synchronization in minutes, if 'Manual only' is choosen, there is no automatic sync but you can use the 'Synchronize now' menu item.
  • Synchronization timespan past (days) and
  • Synchronization timespan future (days): For performance reasons it is useful to sync only a given timespan of a big calendar, especially past events are normally not necessary to sync after a given timespan
  • Deactivate profile: If activated, current profile is not synced anymore without the need to delete the profile
• Advanced Options: Here you can configure advanced network options and proxy settings.
  • Close connection after each request Don't use KeepAlive for servers which don't support it.
  • Use System Default Proxy Use proxy settings from Internet Explorer or config file, uses default credentials if available for NTLM authentication
  • Use manual proxy configuration Specify proxy URL as http://<your-proxy-domain>:<your-proxy-port> and optional Username and Password for Basic Authentication

For Google Calender use the following settings: DAV Url: https://apidata.googleusercontent.com/caldav/v2/<your_google_calendar_id>/events/. Check the Use Google OAuth Checkbox instead of entering your password. When testing the settings, you will be redirected to your browser to enter your Google Account password and grant access rights to your Google Calender for OutlookCalDavSynchronizer via the safe OAuth protocol. For Autodiscovery of all available google calendars use the Url https://apidata.googleusercontent.com/caldav/v2/ and press the 'Test settings' button.

For Google Addressbook use the following settings: DAV Url: https://www.googleapis.com/carddav/v1/principals/<your_google_email>/lists/default/ Check the Use Google OAuth Checkbox instead of entering your password. When testing the settings, you will be redirected to your browser to enter your Google Account password and grant access rights to your Google Calender for OutlookCalDavSynchronizer via the safe OAuth protocol. If you get an error with insufficient access you need to refresh the token by deleting the previous token in C:\Users\<your Username>\AppData\Roaming\Google.Apis.Auth

For Synology NAS with SSL support use port 5006 and the following settings in your NAS: In Synology DSM Navigate to control panel > Terminal & SNMP Select Enable SSH Then enter Advanced Settings and set it to High Now it will work on port 5006 with https.

You can use the exact calendar/addressbook URL or the principal url and use the 'Test settings' button in the option dialog to try to autodiscover available calendars and addressbooks on the server. You can then choose one of the found calendars or addressbooks in the new window. If your server has redirections for well-known Urls (./well-known/caldav/ and ./well-known/carddav/ ) you need to enter the server name only (without path).

You can now set manual proxy settings in the Advanced option dialog in each profile. To override the default proxy settings from Windows Internet Explorer you can also specify settings in the app config file, see config options below. More information can be found at https://msdn.microsoft.com/en-us/library/sa91de1e%28v=vs.110%29.aspx

Options and state information is stored in the following folder:

C:\Users\<Your Username>\AppData\Local\CalDavSychronizer

There is one options_<your outlook profile>.xml file which stores the options for each outlook profile. For each sync profile there is a subfolder with state information stored in a relations.xml file after the inital sync. If you delete that folder, a fresh inital sync is performed.

Each synchronization attempt is logged in the log.txt file. There you can find information about sync duration and the amount of added, deleted or modified events. Errors and Exceptions are logged aswell. For debugging information of caldav requests there is furthermore a logfile log_calDavAccess.txt

In the install dir (The default is 'C:\Program Files (x86)\Gerhard Zehetbauer\CalDavSynchronizer') you will find the app config file

CalDavSynchronizer.dll.config

In that xml file you can config timeout parameters and config options in the section appSettings After changing parameters you have to restart Outlook.

• loadOperationThresholdForProgressDisplay: amount of sync operations to show the progress bar (default 50)
• calDavConnectTimeout: timeout for caldav connects (default 90 sec)
• calDavReadWriteTimeout; timeout for caldav read/write requests (default 5 sec)
• enableTaskSynchronization Support for task sync (alpha) true or false

If you have problems with SSL/TLS and self-signed certificates, you can change the following settings at your own risk. The recommended way would be to add the self signed cert to the Local Computer Trusted Root Certification Authorities You can import the cert by running the MMC as Administrator.

• disableCertificateValidation set to true to disable SSL/TLS certificate validation, major security risk, use with caution!
• enableSsl3 set to true to enable deprecated SSLv3, major security risk, use with caution!
• enableTls12 set to false to disable TLS12, not recommended

In the section system.net you can define proxy settings, e.g. use of NTLM credentials

<defaultProxy useDefaultCredentials="true">
</defaultProxy>

In the section log4net you can define the log level for the main log and for the caldav data access, level value can be DEBUG or INFO