If your BlackBerry stopped synchronizing do the following:
- On the device go to Settings > Options > Advanced Options > Service Books > Scroll to Desktop [Sync].
- Press the track wheel and select "Delete".
- Wait 30 seconds. Press the track wheel and select "Undelete".
- When it is done, press the Escape button, scroll down and select "Enterprise Activation". Wait 30 seconds. The device should start to reactivate without any input from the user.
- When activation is complete test the device.