.ICBU File Extension
File TypeCalendar Backup File
What is an ICBU file?
Calendar archive created by Calendar, a calendar application included with Mac OS X; contains a backup of one or more calendars; used for restoring calendars in the event data is lost.
ICBU files can be created by selecting .ICS files for the calendar events.in Calendar. The export format is actually a folder (with the ".icbu" extension) that contains a subfolder for each calendar and
When restoring backups, Calendar overwrites all existing calendar data. The program prompts the user to overwrite the data before performing the operation.
NOTE: Apple Calendar was formerly known as Apple iCal but was changed in 2012 with the release of OS X Mountain Lion.