How does Synology sync Outlook Calendar and Contact?

How does Synology sync Outlook Calendar and Contact?

Recently, more and more of my friends have been discussing that if it is possiblle to synchronize Synology DSM (such as Synology diskstation DS218+) server’s CalDAV service with Outlook? It looks like this sort of NAS device or router is somehow popular in home and medium-size companies especially where no IT crews are always around. Why? I guess it is because Google Calendar Sync service was terminated 6 years ago and these users have to find another solution.

synology calendar sync outlook

Again, I took this issue to my developer friend in EVO software because their famous EVO Collaborator for Outlook does the Outlook 2007, 2010, 2013, 2016, and 2019 sync thing for living. After some sync simulations, he managed to sync it. Here is what I am allowed to share with you guys if you like to do the same task.

Before we start, there are two points for your reference:
  1. For Synology instruction of setting up webdav, please refer to the following link:
  2. For CardDAV addressbook, it is by default not available in the current version of Synology DSM.
  3. For installing and configuring a third-party CardDAV solution for Synology DSM, please refer to the following link:

Steps to access Synology DSM server’s default CalDAV service with Outlook:

  1. Configure properly in Synology DSM server according to the instruction link shown previoiusly..
  2. Download EVO Collaborator for Outlook from EVO’s Official Site and Install it.
  3. Run Microsoft Outlook 2016/2019 and open Configure Profile(s) at top left within Outlook.
  4. Choose a vacant profile starting with Profile 21 – not configured.

  5. To the top right, leave Hostname (CardDAV/CalDAV) or webcal:// URL blank.
  6. Fill in only Contact and Calendar URL.(URL syntaxes are explained below)
  7. Fill in Full e-mail address or Username and Password.
  8. Click TEST and Apply at the bottom.
  9. Exit the Configure Profile(s) and synchronization will take place in a few seconds.
How to obtain addressbook and calendar URL from Synology server (based on DSM 5.2 or above) ?
  • For contact URL, the URL syntax went as below: (default port is 8443)


  • For calendar URL, the URL syntax goes as below: (default port is 5006)

Steps to access Baikal server on Synology device with Outlook:

By the way, some smart developer put Baikal server on Synology units and use it instead of factory default server. ECO staff thinks some Synology users preferring Baikal server may need it. So, they also make ECO being able to communicate with Baikal server. Here is how:

Enter server host name or IP address in space under Hostname (CardDAV/CalDAV) or webcall:// URL:


Then, enter username and password. Last, click on TEST button to authenticate.

Implementing a server backup strategy

One last thing and the most important task about running a server of any sort is the backup scheme that you use. A backup service that is specifically designed for Synology DSM server is hardly found.





  1. It fails to install caused by missing signature

    1. I just downloaded it and tried installing, it is working now. You can try it again.

  2. This comment has been removed by the author.

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  4. Error installing...
    "Ce paquet ne contient pas une signature numérique"
    (synology 1315+ DSM 5.2-5644 Update 2)

  5. As an alternative you could install OwnCloud on your synology NAS, that is reported to be working and a less buggy alternative to their own CalDav implementation.

  6. I agree with that, owncloud is more powerful and stable.

  7. This comment has been removed by the author.

  8. does it work with the baikal caldav server on my synology?