02-04-2012 01:55 PM
Few scenarios I would think of:
If you are sure you had it and it might have been hidden (accidentally), then, press the menu key and select “show all” and see if you see it.—if you see it, then, select it, then menu key and unhide it.
If your device is working normally and have done a device backup, then, you would do a backup of you device first and then, restore the latest backup file and if it shows up…
--- under applications in options, see if it there?
--- if you use Blackberry Desktop manager, see if you can see messenger as part of the applications.
Finally, if you have run of the options, I would install the lasted device software from the service provide or download it from blackberry website.
Good luck for now.