Try performing the following actions:
- Verify that your SIM card is inserted in your BlackBerry® device correctly.
- Verify that you are in a GSM® or UMTS® network area that is supported by your wireless service plan.
- Verify that the network that you want to connect to appears in your preferred wireless network list.
- On the Home screen, click the Manage Connections icon. Click Mobile Network Options. Verify that the Network Technology field is not set to 1XEV.
- On the Home screen, click the Manage Connections icon. Click Mobile Network Options. If the Network Technology field is set to GSM/UMTS, verify that the Network Mode field is set to 3G & 2G.
Next topic: Power, battery, and memory
Previous topic: I cannot synchronize a certificate