Bugs & Fixes: Dealing with iCal and Entourage duplicates

Suppose you use Microsoft Office’s Entourage to maintain your list of contacts and calendar appointments? Further suppose you wish to sync these data with your iPhone or with your MobileMe account. Can you do it? Yes.

To do so, go to Entourage -> Preferences -> General Preferences -> Sync Services. From here, enable the options to synchronize contacts and events with Address Book, iCal and .Mac (MobileMe).

This is what I’ve done and it works pretty well overall. Except for one persistent and annoying problem: My calendar appointments inevitably begin to reproduce. That is, at some point, I’ll find two of every calendar event in Entourage. At the same time, iCal will show a matching set of duplicates. This replication process expands over time, so that older appointments (ones I have saved past their due date) often wind up with four or six copies.

Who’s to blame for this bug? There is some dispute (see this Apple Discussions thread for example) as to whether the cause lies primarily with Microsoft Office or with Leopard’s Sync Services software. Personally, I give the nod to Microsoft, as I have never had the problem in iCal unless I am syncing iCal with Entourage. What is undisputed is that there is not yet a permanent fix. Neither Apple nor Microsoft appear to be in a hurry to correct the situation.

What can you do in the meantime? Your choices are limited. Either give up on using Entourage for syncing or keep deleting the duplicates as you find them. The latter option can be a time-consuming nuisance, especially if you have a lot of duplicates. If so, try this procedure to eradicate the unwanted copies with a minimum of fuss:

1. Download iCal Dupe Deleter and use it to delete all the duplicates from the Entourage calendar in iCal.
2. Go back to the Sync Services Preferences in Entourage. From here, deselect the sync options and click OK. Return to the dialog to reselect the same options and again click OK. A dialog should appear with three choices (as shown in the screenshot to the right). Select the one to “Delete Entourage information.” In theory, this should immediately eliminate all the events in Entourage, forcing it to repopulate with the duplicate-free data from iCal.

However, when I tried this, and waited about 30 minutes, nothing happened. Growing impatient for results, I tried something else.

I have Apple’s Developer software installed on my drive. Inside the /Developer/Applications/Utilities folder is an application named Syncrospector. I don’t know much about how this utility works. But I know enough to launch it and click its Sync button. That did the trick. I immediately checked back at Entourage and iCal; all the duplicates had vanished.

The entire process, starting with iCal Duple Deleter, should only take about two minutes. There are probably other variations on this theme, perhaps simpler ones, that would have worked as well. But this is what I tried and it worked. Having a way to prevent the duplicates from appearing in the first place would obviously be a preferred solution. Until then, this will do.