The Lightning add-on for Postbox allows you to view your calendar as a separate tab in Postbox. Please note that the Lightning add-on for Postbox is experimental and unsupported at this stage, and this version is currently based on an older Lightning source base.

Lightning is developed by the Mozilla Calendar Team, and while there is a newer version of Lightning available, Postbox does not yet provide support at this time.


1. Download and save the appropriate version to a location on your computer, such as the desktop:

2. In Postbox, go to the Tools menu and select Add-ons.
3. Click the Gear icon or button in the upper right corner, then select Install Add-on From File...
4. Browse to the location of the add-on and select it.
5. Restart Postbox.


If you have already downloaded and installed an earlier version of Lightning, you can automatically upgrade to the latest version by selecting Tools | Add-ons | Find Updates.

Google Calendar

You can use Lightning to connect to your Google calendar (including Google Apps For Your Domain). Just follow these instructions provided by Google.

If you want to access multiple google calendars, install the Google Calendar Provider Add-on for Postbox.

Microsoft Exchange Calendar

You can use Lightning to connect to your Microsoft Exchange calendar using a 3rd party add-on which is currently in BETA and can be downloaded here.

Feedback and Support

For general feedback or to report specific integration issues related to Postbox and Lightning please let us know at our support site.

For issues specific to Lightning, the Lightning team welcomes your feedback in the MozillaZine Calendar Forum or the calendar support newsgroup, however Postbox specific support is not provided.

Known Issues

Here are the known Lightning 1.0b5 issues.

Postbox 2.5 Support

Postbox 2.5 users can use Lightning 1.0b5 with Postbox:

Postbox 2.1 Support

Postbox 2.1 users can use Lightning 1.0b2 with Postbox:

Postbox 1.1 Support

Postbox 1.1 users can use Lightning 0.9.4 with Postbox: