.ICBU File

The icbu file extension is related to Apple iCal (now known as Calendar) in Mac OS X (macOS) operating system.

The icbu file is a backup of calendars, schedules and other tasks saved using the program.

• To back up: Open iCal, then choose Back up Database from the File menu. In the resulting dialog, choose where you want to save the backup file (the current date also gets added to the name) and click Save.
• To restore: Open iCal. From the File menu, choose Revert to Database Backup. In the resulting dialog, locate your backup file (it ends with a .icbu extension), select it, and click Open.

Files with icbu file extension can be found as calendar data backups made in Apple iCal/Calendar program.

How to open:

You can restore these files using the "Revert to Database Backup function"found in iCal.

How to convert:

You can recover *.icbu backups using Calendar/ iCal and then export data to exchange format.