Today - or sometime yesterday, more likely - all of the calendar data disappeared from my handset. The events were still on my Google calendar, but the handset had no data whatsoever (past, present, or future).
Rebooting, the de facto first step for all debugging, did not help. Manually changing something on the Google calendar would refresh that single event on my handset, but no others.
What I didn't see was a way to force a synchronization between my Xperia X10i and my Google calendar. (Why they couldn't have had a "sync now" option like the email app is beyond me.)
The fix is documented in many places, but the best description of the solution I found was over at XperiaX10.net. Here it is, reproduced verbatim from contributor "rookwise":
- Goto settings/applications/manage applications.
- Press the menu button and select Filter and then All.
- Scroll down until you find the Calendar storage application. Select it and clear the data and then select Force Close.
- Next go back to the standby screen and remove the calendar widget (if you use one)
- Next goto the calendar app and open it. The phone will sync the calendar. Press the back button and then re enter the calendar app again.
- Everything should be back as normal.
This worked for me and for many others. The step missing in most of the descriptions available was the "filter" step, which by default hides the Calendar Storage app on the X10, making the solution appear impossible to execute.