After a little searching on the Internet, it appears that the cause of the problem lies in Outlook’s protection measures. Somehow it thought that Google Calendar Sync is broken, and so disabled it to prevent it from killing Outlook. Yes, it did save Outlook and all your calendar items, but syncing now doesn’t work.
So here’s how you re-enable it. In Outlook 2007, go to Help > Disabled Items… then select the Google Calendar Sync add-in to enable. Simple.


A few days ago, Google pushed an update on its Calendar Sync software. So my Calendar Sync software has now been upgraded to version 0.9.3.2. Now, it’s broken, and gives me the error message “Google Calendar Sync: Error syncing your calendar. Error codes: 1011, -2147352567.”

Did anyone else get this problem?
Update: solved.
This is exciting news! Many people use both Outlook and Google Calendar, but there lies a problem: how to synchronise them both? After years of random development here and there across the internet, Google now officially releases a solution to synchronise your Outlook calendar with Google Calendar. It’s about time really, so many people have done the job part way already.
Most solutions have been that you can synchronise one way either from Outlook to Google Calendar, or from Google Calendar to Outlook. Which is simple enough, since it’s essentially a matter of exporting and importing. Other solutions requires the use of a third calendar system that synchronises to both, essentially doing the job of synchronising but you’d get another calendar on top of the two you use already. But the real solution lies at how to synchronise the two calendars without the need for creating a third. This would also extend the usability of Google calendar to sync to other mobile devices through Outlook.
As well as looking at the official Google blog, you might want to take a look at the previous major players in Google Calendar and Outlook synchronisation. Some are even making good money at this: RemoteCalendar, Calgoo, SyncMyCal.
Update: Just installed Google Calendar Sync 0.9.3.0. Everything went smoothly, entered my Google account details, and Outlook 2007 reminders started to pop up out of nowhere. It had actually worked much better and faster than I thought it would. Well done, Google!