As a Blackberry user, you do not want your device to go into SOS mode because the phone will only make emergency calls. When a Blackberry slips into SOS mode, this usually means the device is outside of the network coverage area offered by the service provider, or that the SIM card is defective. You can troubleshoot the issue with a few simple steps. Once the problem has been corrected, the display should say "EDGE" or "GPRS" in place of "SOS."
Turn your Blackberry off.
Take off the battery door and pop out the battery.
Remove the SIM card. Check to see if there are any scratches or signs of damage.
Replace the SIM card and battery, making sure the contacts on the SIM card match up to the contacts on the device. Turn the device back on.
Check to see if the Blackberry is still in SOS mode. If it is, make sure the Network Selection Mode is set to "Automatic" by going to the options menu and selecting "Mobile Network" to view network selection setting. If the network is set to "Manual," change it to "Automatic."
Contact your service provider if the device remains in SOS mode.