This post is part one of a series in which I’ll summarize what I know about publishing calendars openly on the web, for free, using popular calendar applications including Outlook, Google Calendar, and Apple iCal.

Outlook 2007

With Outlook 2007, you can publish for free to calendars.office.microsoft.com. You’ll need a Live ID account. If you don’t already have one, a Live ID is useful for many other services too. To get one, start at login.live.com and click the “Sign up for an account” link.

To start publishing, right-click the name of your Outlook calendar as it appears under My Calendars in Outlook’s navigation pane, select Publish to Internet, and select Publish to Office Online as shown here:

You’ll land on this screen, where — for an open public calendar — you can just click OK and take the defaults.

Now you’ll be prompted for your Live ID credentials.

Enter the email address and password of your Live ID account. And check “Remember my password” so that Outlook can send calendar updates to the server automatically.

Here’s the confirmation:

Even though you likely won’t want to send individual invitations, click Yes anyway. That’s the easiest way to discover what the web address of your published calendar will be. Here’s the email message:

You don’t need to send it anyone, you just need to capture the calendar’s web address. Which, in this case, is:

webcals://calendars.office.microsoft.com/pubcalstorage/
j447ytlz27542/test_Calendar.ics
.

If you publish that link on a web page (more realistically, with a label like Subscribe to calendar), visitors who click the link will be invited to launch one or another calendar program (such as Outlook, or Apple iCal) to view the calendar and subscribe to updates. That same address can be used by online services like http://elmcity.info/events which combine calendars from multiple sources.

The .ics in test_Calendar.ics stands for Internet Calendar Standard. The ICS file is useful for exchanging calendar information among calendar programs that run on personal computers, and among calendar services that live online. But it’s not something people can view directly on the web. For that, you’ll want to use a variant of the address that produces a web page people can see and interact with. Here’s the variant:

http://calendars.office.microsoft.com/en-us/pubcal/viewer.aspx?path=
/pubcalstorage/j447ytlz27542/test_Calendar.ics

To form your version of this link, copy the initial part of the above link — the part that isn’t bold — and then replace the part that is bold with the corresponding part from the invitation email shown above.

If you then publish that link on your website, it will lead visitors to a page like this:

Visitors to that page can view the calendar in several ways. And they can subscribe to the calendar by clicking the Subscribe link.

Earlier versions of Outlook

I’m still researching the options. Comments welcome.