SolutionBase: Let your schedule fly free with Sunbird first challenged Microsoft on the browser front with FireFox. Then, it released Thunderbird to compete against Outlook. Here's a look at's calendaring program.

For a few years now, has been challenging Microsoft products by releasing open source versions of popular Microsoft software. It began by creating Firefox, an open source Web browser to oppose Internet Explorer. Then, it followed up by releasing Thunderbird as an alternative to Outlook and Outlook Express.

With confronting Microsoft on the office front, what's left? Calendaring for one. Outlook has a very powerful scheduling and calendaring tool that's still lacking in OpenOffice. now fills that hole with Sunbird.

What's Sunbird?

Sunbird is an open source calendar program that's supposed to adhere to the iCalendar standards. iCalendar is a standard format for the exchange of calendaring information created by the Internet Engineering Task Force. Ideally, any calendar program that uses the iCalendar standard can exchange scheduling information with any other compatible calendar.

Microsoft Outlook's calendar format is completely proprietary. As such, when you create schedules in Outlook, you can only access those schedules using Outlook or Entourage, a Mac OS X program written by Microsoft itself.

Outlook can support the iCalendar standard, but it has problems with the standard. Outlook 2000 in particular has errors in its support that can prevent it from processing iCalendar based schedules.

Sunbird is actually one-third of's calendaring effort. also ships Lightning and Calendar. All three of these programs share the basic code, but they're different at the same time. Sunbird is a standalone program. Calendar is an extension for Firefox. Lightning is an extension for Thunderbird,'s email program. For the purposes of this article, we'll focus on the Windows version of Sunbird.

Obtaining and installing Sunbird

You can get Sunbird from the Sunbird Web site on Currently, the program is in alpha, so that means that the actual version you'll download will vary. The current version is Sunbird 0.3 alpha1.

Click the Windows Installer link. You'll then download the EXE version of the Sunbird installer. It's a small file, only 4.8Mb in size, so it won't take too long to download. Once you've downloaded it, simply run it to install it.

Sunbird installs using a typical Windows installer. There aren't any gotchas or anything to worry about. At the end, you have the option of locating a Sunbird icon on the desktop and in on the Quick Launch bar.

Running Sunbird

To start Sunbird, click its icon. Sunbird loads a very simple calendar page when it starts, as you can see in Figure A.

Figure A

Sunbird has a very clean interface.

You can change the display to show daily, weekly, multi-week, or monthly calendars. Double click a date to have a detail page for it to appear.

It's very simple to create new events. Simply click the New Event button and fill out the information on the screen that appears. You can invite others by clicking the Attendee tab. You'll need to know the email address of the person you want to invite. Likewise, you can create new tasks.

Extending Sunbird

Sunbird shares Firefox's and Thunderbird's abilities to add extensions and change the theme. Simply select Extensions or Themes from the Tools menu. Sunbird uses the same themes and extensions as Firefox, but because it's an alpha, you should probably avoid using any extensions or changing its theme.

Sunbird caveats

Sunbird is a pretty good piece of software, but it's not perfect. Because it's an alpha, programmers are still busy ironing out some bugs. Some common bugs in Sunbird include:

  • Windows versions of Sunbird 0.3 alpha1 will crash for dates after 2037 and before 1970.
  • Switching from Task to Event in the Event dialog fails
  • Attachments cannot be added to events
  • Printing support is limited
  • Alarms can only be snoozed for 5 minutes
  • Alarms missed while Sunbird was closed will not be fired
  • Email alarms do not work in Sunbird
  • Publishing errors will be reported poorly
  • The timezone preference does nothing
  • Unchecking a calendar may cause a Javascript error

Long ways to go

Sunbird and its relatives are still in alpha-release. As such, there's still a long way to go until they're complete. Even in this form, Sunbird shows much promise and is a good alternative if you want to go open source for your calendaring solution.