This article describes how to add a holiday calendar to the latest version of [https://addons.mozilla.org/en-US/thunderbird/addon/lightning/ Lightning] (a popular calendaring add-on for Thunderbird). __TOC__ = What is a holiday calendar? = A holiday calendar lists all the public holidays of a country and displays these in Lightning. Many national holiday calendars are available on the [http://www.mozilla.org/projects/calendar/holidays.html Mozilla Holiday calendar page]. = Installing a holiday calendar = You can either download and import a calendar into Lightning or you can simply subscribe to a calendar by copying the URL and then adding it as a new remote calendar file. == Install the calendar locally == With this method, the calendar file is stored on your hard disk and will be available even if you are offline. You will also be able to modify it (for example, by adding provincial or state holidays to a national holiday calendar). Follow these steps to install a holiday calendar: #Visit the [http://www.mozilla.org/projects/calendar/holidays.html Mozilla holiday calendar page] or another site that offers national holiday calendars. (Calendar files have the suffix ".ics".) #Right-click the link of the holiday calendar you want to install and select {menu Save Link As...}. #If necessary, open Thunderbird. (Lightning must already be installed.) #Open the {menu File | Open | Calendar file} menu option. #Select the calendar file that you have saved on your disk during step 2. You will see that a new calendar with all your holidays has been added to your calendar view. == Subscribe to a remote calendar == With this method, you will subscribe to a calendar file that is published on the internet. The calendar will be kept up to date by its maintainer. Follow these steps to subscribe to a remote holiday calendar: #Visit the [http://www.mozilla.org/projects/calendar/holidays.html Mozilla holiday calendar page] (or another site that offers national holiday calendars) and right-click the link of the holiday calendar you want to install and select {menu Copy Link Location}. #If necessary, open Thunderbird. (Lightning must already be installed.) #Switch to calendar view by clicking the Calendar icon next to the tab bar. Next, go to the {menu File} menu, select {menu New} and select the {menu Calendar...} item. #In the ''Add a calendar'' wizard, select {menu On the Network} and click {button Next}. #From the ''Format'' list, select {menu iCalendar (ICS)} and enter the calendar location that you just copied into the ''Address'' textbox. Click {button Next}. #Give the holiday calendar a name or leave the default value. If you want, you can select a color in which all of the holidays are highlighted. Click {button Next}. #Click {button Finish} to exit the wizard. This will now load the holiday calendar. Lightning cannot determine when you are using a remote calendar, so you should double-click on the calendar name and check the box called '''Read Only''' in order to lock the calendar. If you don't do that, you will be able to change or delete any event, but all your changes will be lost when Thunderbird restarts.

This article describes how to add a holiday calendar to the latest version of Lightning (a popular calendaring add-on for Thunderbird).

What is a holiday calendar?

A holiday calendar lists all the public holidays of a country and displays these in Lightning. Many national holiday calendars are available on the Mozilla Holiday calendar page.

Installing a holiday calendar

You can either download and import a calendar into Lightning or you can simply subscribe to a calendar by copying the URL and then adding it as a new remote calendar file.

Install the calendar locally

With this method, the calendar file is stored on your hard disk and will be available even if you are offline. You will also be able to modify it (for example, by adding provincial or state holidays to a national holiday calendar).

Follow these steps to install a holiday calendar:

1. Visit the Mozilla holiday calendar page or another site that offers national holiday calendars. (Calendar files have the suffix ".ics".)
2. Right-click the link of the holiday calendar you want to install and select Save Link As....
3. If necessary, open Thunderbird. (Lightning must already be installed.)
4. Open the File | Open | Calendar file menu option.
5. Select the calendar file that you have saved on your disk during step 2.

You will see that a new calendar with all your holidays has been added to your calendar view.

Subscribe to a remote calendar

With this method, you will subscribe to a calendar file that is published on the internet. The calendar will be kept up to date by its maintainer.

Follow these steps to subscribe to a remote holiday calendar:

1. Visit the Mozilla holiday calendar page (or another site that offers national holiday calendars) and right-click the link of the holiday calendar you want to install and select Copy Link Location.
2. If necessary, open Thunderbird. (Lightning must already be installed.)
3. Switch to calendar view by clicking the Calendar icon next to the tab bar. Next, go to the File menu, select New and select the Calendar... item.
4. In the Add a calendar wizard, select On the Network and click Next.
5. From the Format list, select iCalendar (ICS) and enter the calendar location that you just copied into the Address textbox. Click Next.
6. Give the holiday calendar a name or leave the default value. If you want, you can select a color in which all of the holidays are highlighted. Click Next.
7. Click Finish to exit the wizard.

This will now load the holiday calendar. Lightning cannot determine when you are using a remote calendar, so you should double-click on the calendar name and check the box called Read Only in order to lock the calendar. If you don't do that, you will be able to change or delete any event, but all your changes will be lost when Thunderbird restarts.