08-17-2009 02:50 PM
Welcome to the BlackBerry Support Community Forums
You should be able to reinstall it by downloading the latest version of device software from your wireless provider's website:
Also make sure you have the Desktop Manager software installed that came with your BlackBerry.
Using the Application Loader icon in Desktop Manager, you should be able to reselect BlackBerry Messenger from within the Device Application Selection screen and reload it onto the device.
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