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When you place an active UK SIM into an unlocked mobile phone, SMS will be available immediately. If they are not, you should be aware of some standard troubleshooting

Diagnosing the Issue

         Messages I send are not being received

         I cannot receive messages

         I am receiving duplicate messages

         Messages I send are being duplicated

         I’m getting error messages


Standard Diagnostics

  • Reboot your mobile device
  • Perform a hard reset
  • Is your phone still in flight–mode?

Reboot your mobile device

Switch off your mobile. The method will vary per phone model but is usually either by holding a button on the top or by touching the screen or a keyboard button.

Wait for around 30 seconds before turning your mobile back on. This will ensure that the connection has completely died and that the signal is refreshed.


Switch on your mobile. This is usually by repressing that same button on the top of the phone.

Wait again for around 30 seconds. The signal should now have refreshed and you can successfully make calls.


It is generally recommended by mobile phone manufacturers that you do this once a day to ensure the best connection and quality of service from your phone.

Perform a hard reset

BlackBerry devices

Either power down as above or hold down the ‘Alt’, the ‘Shift’ and then the ‘Delete’ keys in sequence. If this doesn’t work you can remove the cover, take out and replace the battery and your Blackberry should restart.

Other devices

Remove the cover, take out and replace the battery and power the device back on.

Is your phone still in flight mode?

In flight mode all wireless connections are turned off, so your phone can’t cause any interference with sensitive equipment in a plane or a hospital. You can still use your phone when flight mode is turned on, but you can’t send messages or make calls. Follow these instructions to turn flight mode on or off.

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