I have been working for hours to solve this problem. 

![enter image description here](https://i.stack.imgur.com/6fUJ1.png)

As you see above, I got CMS error 321

explanation of the eror code 321

The memory/message storage index assigned to the AT command is invalid.

source: <http://www.developershome.com/sms/resultCodes2.asp>

With that code, I wanted to get message count, and to read sms and I got the same error.. 

I can send sms with AT commands but I want to read sms from mobil phone. I connected via usb and bluetooth, and the result is the same.. I can send sms but cant read sms .. 

What is the wrong on it? 

For reading sms I use that code

AT+CMGL="ALL" or "REAC UNREAD" .. etc.

I've used Samsung Galaxy S I9000 and HTC Evo 3d