I developed an SMS application using VB.NET. I'm able to apply all the AT commands related to send and receive SMS. My problem would be sometimes if I send an SMS, the SMS being displayed on the recipient's phone is

' AT+CMGS=" +6581XXXX" > Hello World '

How can i make my program assures that the string being sent out from my modem is "Hello World" only? And what are the possible causes of this kind of problem where it sends out the whole AT command to recipient instead of the msg only?