How to avoid duplicate generated calendar entries? I'm using Google Calendar on my desktop computer. It seems to auto-generate birthday entries for my contacts in Google Mail. Unfortunately these entries show up twice in "My calendar" in the generic Calendar app (version 1.1) of Android 4.0.4. How can I avoid this? 

I don't see any duplicate entries in other calendars, and the calendar list only shows "My calendar" once.

Written on my Samsung SII :-)
Here are some options you can try:


Remove your Google account and adding it back. Source
Clear app data via Settings &gt; Application manager &gt; Calendar Storage &gt; Clear data. Source.
UPDATE 2013-05-15: This worked for l0b0