Sharing internet calendars

In this article, we'll look at how to share calendars using Outlook, but without the need for Microsoft’s Exchange Server and the expense and complexity that can entail. More specifically, I want to look at how you can use the Internet Calendars option in Outlook 2007 to achieve this goal.

Outlook 2007 lets you share calendars in two ways, the simplest of which is to take one-time snapshots which can then be emailed to other people, including those using Outlook 2003.

That, however, doesn’t deliver very much, as the information in a snapshot goes out of date very quickly.

Rather, to share calendars more fully, you need a web server to which calendars can be published. Other users of Outlook 2007 can then subscribe to those calendars and automatically receive updates when changes are made to the original, and it’s this, second option, that I want to examine in more detail here.

Choose your server
One way of publishing calendars is to use the free calendar sharing server available from Microsoft via its hosted Office Online service. Sign up, then follow the instructions provided.

Alternatively, you might prefer to keep Microsoft (and the internet) out of the loop and use a local web server of your own.

In that case, you’ll need a web server that supports the Web Distributed Authoring and Versioning protocol (WebDav), to enable documents and other files to be shared using HTTP on port 80. It’s an option that may sound a little involved, especially if you’ve never configured or run your own web server (let alone a WebDav one), but in practice it’s really very easy.

Installing IIS
The first thing to understand is that if all you want to do is share calendars on a home or small-office network, then you don’t really need a big server. A desktop PC will do, and it doesn’t need to be dedicated to the task.

Moreover, you don’t need Windows Server, as the software required – IIS (Internet Information Services) – is included as part of both Windows XP and Vista. All you have to do is install it.

In the examples here I’ve used an XP professional PC on which I’d previously configured an Imap email server using the free hMailServer software. It makes sense to put the web server on the same host; to install the IIS software I simply went to the Control Panel, double-clicked Add or Remove Programs and chose Add/remove Windows Components.

Internet Information Services was included in the list of available XP components although I didn’t need everything that’s packaged as part of this option.

The SMTP mail server, in particular, does little more than take up memory space and is totally unnecessary when running a third-party email application, so it’s a good idea to click the Details button and uncheck this option.

That done, Windows will install the IIS software and start it running for you without having to reboot. In my case I needed the installation CD, but on a lot of PCs the install files will be on the hard disk already and nothing else will be required.

WebDav support is included in the IIS 5.1 software that comes with XP, so you don’t have to do anything other than install IIS to use it. It’s also in the Vista and Windows Server versions, but in more recent releases of the server OS you may have to install and/or enable WebDav support independently before it can be used.
WebDav is also available for Apache and other Linux Web servers.