Unable to send e-mails from a Blackberry with event ID: 20209 warnings logged on the BES 4.x server’s application logs

I ran into an issue today that I have come across before but did not remember how to fix it and since I know I’m bound to run into this situation again, I thought it would be a good idea to blog it.

Problem

You have a user who has a Blackberry that is unable to send e-mail messages but is able to receive messages.  Logging onto the server and reviewing the application logs shows that several event ID: 20209 warnings are logged stating the following:

{UserFirstName UserLastName} DecryptDecompress() failed, Tag=159789, Error=604

Solution

The reason why this message would be logged is if there is a problem with the encryption key between the device and BES and to correct this problem, all you need to do is manually regenerate the encryption key on the user’s Blackberry by navigating to Options –> Security Options –> Information then scroll down to the Services section, highlight the Desktop line item, click and select Regenerate Encryption Key. This will force a regeneration of the encryption key so the user can send emails from their Blackberry again.