If a user’s default calendar is not visible to the Communications Express user interface client, but still exists in the database, you can recover the calendar and make it visible again by updating two attributes in the user’s LDAP entry.
To recover a calendar, make sure the value of the following attributes in the user's LDAP entry is the user's fully qualified calid:
For Schema version 2, use one of the following methods to update the attributes:
Use the ldapmodify Directory Server utility.
Use the Calendar Server Utility command csuser reset.
Use the Delegated Administrator Utility command commadmin user modify.
Use the Delegated Administrator Console to add the default calendar name by editing the User Properties page.
For Schema version 1, use the csattribute add command to update the attributes.