Hack 76. Ping a User s BlackBerry

Hack 76. Ping a User's BlackBerry

Send a specially formatted email message that a BlackBerry will automatically confirm delivery of.

As a BlackBerry administrator, you often get calls from users claiming they are not receiving messages on their devices. Of course, there are several reasons a user might find himself in this situation; for example, he could be in an area that has no wireless coverage. Surprisingly, often a BlackBerry Enterprise Server user's device will be cradled with the "Disable email redirection while your handheld is connected" option selected in the user's Redirector Settings.

It would be nice if the BlackBerry operating system could confirm receipt of an email via an autoreply message. It turns out there is such a feature that comes in quite handy.

7.6.1. Send the Message

Just compose a message with the string <confirm> in the beginning of the subject, as shown in Figure 7-8. When the BlackBerry device receives a message with this in the beginning of the Subject field, it knows to send a reply to the sender with a confirmation that it has received the message (see Figure 7-9).

Figure 7-8. Sending a message that will be confirmed

Figure 7-9. Delivery to handheld confirmed

This feature is also good for sending important messages to users who are traveling and may be out of the coverage area. The reply confirms that they have indeed received the message to their handheld of course, there are no guarantees that the user will read the message, however.

For BES users, you can request a read receipt that the BlackBerry will respect when the user reads the message.

7.6.2. Hack the Hack

There is another option you can include in the subject that controls the behavior of messages sent to the BlackBerry. You can add the removeondelivery option to the message subject to have the handheld delete the message immediately after receipt. This is useful to unobtrusively send a test message to a user without having the user actually see the message. Use the subject as follows (notice the dollar sign preceding the first option when multiple options are used):

 <$confirm,removeondelivery> Actual Message Subject 

If you're using a version of the BlackBerry Enterprise Server earlier than 4.0.2, the message will be deleted on the server inbox but will remain on the handheld. This is because the BES performs a "hard delete" on the message, bypassing the Deleted Items folder entirely. On a pre-4.0.2 BES server, only messages that are "soft deleted" (that is, moved to the Deleted Items folder) are deleted from the handheld when Wireless Reconciliation is turned on. Starting with 4.0.2, the BES is supposed to sync the hard deletes as well as soft deletes.