If you loose sync (email, contacts or calendar) and are on a BES but don't want to bother with a support call you can try this trick to do your own Enterprise re-Activation. Go to the Options/Advanced Options/Enterprise Activation menu. In the email field type in CNFG while holding the Alt key. After typing this, you should have a new menu appear. From that menu, change the option for Wireless Sync from On to Off and then exit the menu while saving changes. Give the phone about half a minute and then go back into the menu and change the Wireless Sync to On. Exit and save changes again and it should then start the process of Activating. This, as well as taking the battery out and putting it back in will fix 90% of corporate blackberry issues
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