Installing Lightning into Thunderbird

This article is no longer maintained, so its content might be out of date.

This article explains how to install Lightning into Mozilla Thunderbird.

Lightning and Thunderbird 38

Starting with Thunderbird 38, Lightning is bundled with Thunderbird. This means you don't need to install it separately, but simply confirm to use it once you create a new profile or upgrade from a previous version of Thunderbird.

For previous versions of Thunderbird, the below still applies. The same may be true for Thunderbird 38 for builds distributed by third parties.


The current released version of Lightning always requires the current released version of Mozilla Thunderbird (but older versions of Lightning are available for previous versions of Thunderbird). E.g. as of March 13, 2012, the current version of Thunderbird was Thunderbird 11 and the corresponding current version of Lightning was 1.3 and Lightning 1.2 was for Thunderbird 10 and so on.


You can download the latest released version of Lightning or the latest Development Channel build. The Development Channel build has more features than the latest stable release but might have severe bugs that can cause data loss or crash your application. This build is designed for those testing development builds of Thunderbird

IMPORTANT: Don't use the Development Channel builds with production data as data loss and other scary things can occur. If you do not want to risk any data loss, please use the latest released version.

Download links:


IMPORTANT: If you have been using the old Calendar Extension, be sure to backup the ICS file that it put in your profile directory and uninstall the Calendar Extension before installing Lightning. After you have installed Lightning, you can then import your old events and tasks from the backed up ICS file.
  1. In Thunderbird, open the extension manager using the Tools menu and clicking the Add-ons menu item.
  2. Click the Install… button in the lower left hand corner of the Add-ons box.
  3. Locate and select the file you downloaded and click OK.
  4. Close and re-open Thunderbird to finish the installation.
  5. Please read the Lightning release notes before you use this software.

Congratulations, your calendar should now be correctly installed! You find additional information in the Use the Lightning Calendar Add-on article.

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