How to wirelessly delete the calendar data on a BlackBerry smartphone
 

RIM KB Article 15139

Warning: The following procedures will delete either all data, or all data and applications on the BlackBerry smartphone. Back up the data prior to performing the procedure. For instructions, see KB12487.


Procedure

Complete the steps for the version of BlackBerry Device Software installed on your BlackBerry smartphone.
BlackBerry Device Software 4.2.x

On the BlackBerry smartphone, complete the following steps:

1. In the menu of the calendar, select Options.
2. Scroll to the bottom of the screen, and type RSET.

Note: For BlackBerry smartphones that support SureType® technology, use the multi-tap input method.
BlackBerry Device Software 4.3.x

On the BlackBerry smartphone, complete the following steps:

1. In the menu of the calendar, select Options.
2. In the Options screen, type RSET.

Note: For BlackBerry smartphones that support SureType technology, use the multi-tap input method.


Additional Info
Wireless calendar synchronization is turned on

If wireless synchronization of the calendar is turned on, the following message will appear:
This will erase your <nameofcalendar> calendar, and reload it from your server. Continue?

After the calendar data has been deleted, the following message will appear:
The <nameofcalendar> calendar has been wiped. It will be repopulated from your server.

The calendar will be repopulated with calendar data from the server.
Wireless calendar synchronization is turned off

If wireless synchronization of the calendar is turned off, the following message will appear:
Wireless Calendar, for <nameofcalendar>, is not enabled. Wipe Calendar anyway?

After the calendar data has been deleted, the following message will appear:
The <nameofcalendar> calendar has been wiped.

The calendar will be repopulated with calendar data using BlackBerry® Desktop Manager.
Repopulation of calendar

During the repopulation of the calendar, the following message may appear on the BlackBerry smartphone:
Organizing Calendar

The performance of the BlackBerry smartphone may be affected during the repopulation of the calendar. The speed of repopulation depends on the amount of data transmitted and the speed of the wireless network.

Good stuff!
Thanks for pointing this out, h.

Is there a similar method for the individual synchronizable applets - i.e. tasks, memos, contacts? I tried it for contacts, but did not seem to work. OS on the BB is 4.2.1.110.