You can't send text messages after upgrading ios7. 1 for the US version 4s with lock and the V version.

I have a way to send text messages, but I can only connect to the 2G network, and everything else is normal (just don't have to escape):

1, Settings-Mobile phone -sim card application 3to2, 3to2 becomes * 3to2, please operate this before restarting the mobile phone.

2. When the iPhone is connected to WiFi, use the safari browser on the iPhone desktop to directly input the 3to2.china3gpp.com online installation patch.

3. After installing the patch, the "GPP 3to2" software will appear on the mobile phone desktop.

Then open: "GPP 3to2" software; Click "Open Patch/Patch"; Pop-up: "Go to 2OK" to open the patch for 3 times! ! ! (If there is no prompt, please close the software and repeat the operation. )

4. Finally, insert the card sticker with sim card into the mobile phone, restart the mobile phone and wait for the signal.

Note: The mobile phone has 3to2 software to delete and reinstall. Click "Open Patch/Patch"; Pop-up: Open the patch 3 times by "Go to 2OK".

5. Then the mobile phone is restarted, the signal is displayed, and E is displayed. You can also send text messages. This method was bought by Taobao. Just now, the seller said it could only be moved, but I tried Unicom Mobile.

You can read this post: /p/3 1037 16752.

I hope I can help you. My 4S is also solved in this way.