title: C# send text msg/sms via USB-HSDPA Modem -> unsupported message type
body: <p>I am trying to create a text msg/sms gateway using a USB-HSDPA Modem from Huawei (E122-1).
  I have done this with an older Modem some time ago. After some troubles installing the driver and receiving the correct comPort of the new device I have finally established to communicate with the device.</p>
  
  <p>comPort Check and PIN-Check are already done.
  Now I'm switching to textmode (CMGF) and write the message (CMGS):</p>
  
  <blockquote>
    <p>comPort.Write("AT+CMGF=1\r\n");<br>
       Thread.Sleep(1000);<br>
       comPort.Write("AT+CMGS=\"" + "some tel no" + "\"" + Environment.NewLine);<br>
       comPort.Write("text content" + (char)26 + Environment.NewLine);<br>
       Thread.Sleep(2000);<br>
       response = comPort.ReadExisting();</p>
  </blockquote>
  
  <p>everything works fine, i get proper responses and everything.</p>
  
  <p>BUT, here is the problem: the sent text message can't be read on all mobile phones/smart phones:<br>
  - my old Nokia 6300 says 'unsupported message type'.<br>
  - HTC Desire shows an empty message.<br>
  - Samsung Galaxy S2 'content is not supported'.<br>
  - Samsung Galaxy S shows the message just fine.   </p>
  
  <p>Now here is the weird thing, if i use the application which comes with the modem (t-mobile austria internet manager) to send a text message, all of the listed devices can display it correctly.</p>
  
  <p>am I missing something with the encoding or some kind of a header? (which the 't-mobile internet manager' apparently is using for correct displaying of the text message at the receiver side)</p>
  
  <p>any suggestions or ideas?</p>
  
  <p>thanks,
  Sise</p>