Extend Thunderbird with Calendar and Address Book synchronisation. The below guide contains information to setup a connection to an owncloud server, but any other CalDAV and CardDAV server would work as well.

1. Install Thunderbird or the Portable Edition
2. If you are porting your Email from Outlook, convert the Outlook PST or OST files to Thunderbird MBOX format with PST Viewer from PST Walker Software. You need a 50 USD home license to convert PST files, and a 75 USD business license to convert OST files.
3. Copy all files created by PST Walker for one account into Thunderbird\Data\profile\Mail\<your-mail-account-directory>.
4. Download the SOGo Connector with a right-click on the button, then install it from file in Thunderbird. See details below.
5. As of Thunderbird Version 45, the Lightning extension is already installed. This extension provides Calendar functionality.
6. Click on the Calendar icon on the upper right side of the Thunderbird window to open the Calendar tab. Right-click the default calendar in the left pane, or right-click into the empty space in the left pane to create a new calendar, and enter the path to the DAV server in field Location.
7. You don't need to worry about the credentials if you already setup the SOGo Connector, it will take care of it.
8. Note that during the first sync of the calendar, Thunderbird will freeze and become unresponsive, unfortunately there is no progress bar or information displayed. Just wait until Thunderbird becomes responsive again, which indicates the calendar sync has been completed.
9. If you are using Thunderbird Portable, register it as default mail program in Firefox or Firefox Portable. Select Options –> Applications, then click on mailto and browse to the location of Thunderbird Portable.

You need to connector to be able to synchronize with DAV server.

1. Download the SOGo Connector with a right-click on the button, then install it from file in Thunderbird.
2. Restart Thunderbird.
3. Open the Address Book, then select File –> New –> Remote Address Book
4. Enter a Name, for example Contacts, and the URL to DAV server. Leave the Periodic sync off for now. Save the new address book.
5. Right-click on the new address book, then Synchronize. Thunderbird will now ask for the access credentials to your DAV server, enter them, and select save to Password Manager. This way, you will not need to enter the credentials repeatedly for Address Book and Calendar sync.
6. After the first manual sync, change the settings of the Address Book to Periodic sync.

• ownCloud - https://cloud.condrau.com/remote.php/dav/addressbooks/users/<user>/default/
• Synology DSM - https://cloud.condrau.com:8443/addressbooks/users/<user>/addressbook/

• ownCloud and iPhone Setup (ignore the first paragraph on OutlookDAV)
• Synchronize SOGo contacts with Mozilla Thunderbird address book
• How To Sync Calendars In Thunderbird Using CalDav
• Sharing a profile between Windows and Linux