I recently had an excellent discussion with Dominique Parris, a reader of this column, about how Microsoft Office Outlook 2007 synchronizes with SharePoint—which is different from what we're used to when using Outlook 2007 to download email, and from how Outlook 2003 synchronizes with Windows SharePoint Services 2.0. We discovered some very interesting details and insights that I'd like to share with you.
If you've seen my previous columns on SharePoint and Outlook 2007 integration, you should already know how to enable synchronization, but I'll mention it for anyone who hasn't done it before. All you need to do is select the desired list in SharePoint and select "Connect to Outlook" on the Actions menu. (For more information, see "SharePoint Integration with Outlook 2007, Part 1," April 27, 2007, and the other articles you'll find in the Learning Path on that page.)
Offline synchronization was introduced with Outlook 2003, giving read-only access to certain lists, such as Calendar and Contacts. In Outlook 2003, you can define the synchronization frequency using the STSSyncInterval registry subkey as described in the Exchange & Outlook Administrator article "SharePoint Offers a Different Outlook," February 2006. During every sync cycle, Outlook 2003 updates all lists.
However, when you're using Outlook 2007 combined with Windows SharePoint Services 3.0, you'll find the registry subkey doesn't exist anymore. You configure SharePoint list synchronization as part of Outlook 2007's Send/Receive Groups dialog box, which you'll find by selecting Tools, Send/Receive, Send/Receive Settings, Define Send/Receive Groups. Under Setting for group "All Accounts," you can define a sync interval by selecting the Schedule an automatic send/receive every x minutes check box and updating the time as appropriate. You might think that if you configure your default All Accounts group to automatically send and receive every 15 minutes, for example, you'll download any updates from the SharePoint site at this interval. However, Dominique and I discovered a different behavior: If you open a SharePoint folder in Outlook (e.g., the calendar), then create an item on the SharePoint site, the new item won't be downloaded automatically.
It took some more testing before we found out how Outlook 2007 synchronizes these items. A full synchronization, including an update to all your registered SharePoint lists or document libraries, takes place
A synchronization of the current list or folder takes place
when you click on a list or document library to view it
when you create, modify, or delete an item in Outlook
when you enable shared content (e.g., Calendar, Contacts)
You'll see the Send/Receive status on the lower right corner of the Outlook window as it synchronizes. If you open the Send/Receive Progress window (Tools, Send/Receive, Send/Receive Settings, Show Progress), you'll see the SharePoint sync displayed on the Tasks tab. It's important to remember that Outlook 2007 doesn't use your established synchronization cycle for downloading SharePoint content.
I assume the basic logic for this sync strategy is that synchronization takes place only when you first log on and when you access a folder; if you don't access something, no sync is triggered. This strategy makes sense because if you've integrated many SharePoint lists from different SharePoint sites, synchronizing all of them every Send/Receive cycle could cause network congestion and would also reduce SharePoint's performance. But it can be a little irritating because the process is different from what you expect. As Dominique put it, "The current behavior does seem logical. Why change anything if nothing's been changed?"
