Sharing internet calendars

Preparing your server
Once your web server is up and running you’ll need to go through a few more steps to get it ready to publish calendars. The tool to use here and how it’s accessed will depend on the version of IIS involved, but on an XP system go to the Control Panel, select Administrative Tools then Internet Information Services, which will start the Microsoft Management Console with the appropriate IIS plug-in.

Using this tool the first thing required is a virtual directory to hold your calendars, something you do by right-clicking the default website then pointing to New and clicking on Virtual Directory.

A wizard guides you through the process and in my example I gave the virtual directory an alias of CalendarShare then pointed it at a folder in the root of my boot disk (C:\CalendarShare), which needs to be created in advance.

The wizard also asks you to set the access permissions for the virtual directory. However, by default, it makes the directory read-only so and I’ve added Write access to enable calendars to be published to this location.

Finally, you may want to change the way IIS authenticates users. That’s because, unless otherwise specified, any virtual directory created will allow anonymous access, effectively authenticating everyone using just one user account called IUSER, created when IIS is installed.

That may be fine on a home network, in which case leave it alone. However, if you’re sharing calendars on a small-business Lan or using a web server that also hosts publicly accessible sites you’ll want to change this setting.

To do that right-click the virtual directory, select Properties and choose the Directory Security tab. Click the Edit button and un-check the Anonymous Access option, after which you can opt for Integrated Windows Authentication - in other words, identify users by the username specified when they log onto Windows.

Do, though, make sure that simple file sharing is disabled in XP, as this option can prevent WebDav using Windows Authentication properly.

Publishing a calendar
Having prepared the web server, you’re now ready to start publishing calendars. Any calendar created in Outlook 2007 can be published, and you can publish as many as you want.

Simply go to your list of calendars, right-click the one you want to share then select Publish to Internet followed by Publish to WebDAV Server. The Publish Calendar to Custom Server window will open and you can type in the URL of your IIS virtual directory in the Location box. In my example, the XP PC running the IIS Web server on my Lan is called Grumpy so the URL I’ve used is http://Grumpy/CalendarShare.

You can also specify the time span you want to include in the published calendar and the level of detail. The options include the ability to simply show time as “Free”, “Busy” and so on; display the subjects of calendar items or include all the available detail – except for attachments, which can’t be published.

By default a published calendar will be updated automatically but if you click the Advanced button you can turn this off and only upload it to the server once. You can also choose to only update the published calendar when you send/receive mail from the Outlook application rather than using the built-in update interval.

Lastly, when a calendar is first published you’re prompted to send an email to the people with whom you want to share it. If, however, you want to add others later on simply right-click the calendar, point to Publish to Internet and select Share Published Calendar to issue more invitations.

Subscribing to a calendar
When a user receives an invitation it’s just a matter of clicking on the link provided to subscribe to the calendar held on the server. Outlook 2007 will then add it to the calendar list, after which the user can browse and search the calendar as normal and drag entries from the shared calendar to others of their own.

Unless otherwise specified, any changes made to the original will be automatically downloaded from the web server.

But it’s not all sweetness and light, the biggest issue being that subscribed calendars are opened read-only so it’s not possible to add or modify entries. That’s not a problem if you just want other people to see what’s in your calendar. But it could be an issue if you want to an assistant to manage your diary, or for everyone to be able to record what they’re up to in a single shared office calendar.

Bear in mind, too, that there’s no support in Internet Calendars for setting up meetings and other events, or inviting people to those events and automatically checking for free time slots. For that you’ll need Exchange or another backend application able to handle the processing involved.

Outlook and Google
Users of Google Calendar (in beta at the time of writing) can import calendars created in Outlook 2007 by first saving them in the iCalendar (or iCal) format.

To do this open the Outlook calendar you want to transfer, then go to the File menu and select Save As. The only option you’ll get is to save in iCalendar format, but by clicking More Options you can specify the date range and the level of detail you want to include, just as when publishing a calendar using Internet Calendars.

Once you’ve saved the calendar as an iCalendar file you can then open a browser and logon to Google Calendar. Click on Settings and select the Calendars tab and you should find an option marked Import calendar. Click this and you’re prompted for the name of the iCalendar file to import and the name of the Google calendar into which the information will be inserted. Click the Import button and you’re done.