activate auto/sensitive suggestion box

[kimoalking]

hi. I installed visual studio 2010 ultimate. and I'm using Visual C++ window form application. I'm making a web browser.using 3 buttons(back,forward, and go), 1 text box, and 1 webbrowser. during the codding in a back button for example: when I write
this->
suppose to be a sensitive suggestion box appear that recommend me to choose one of them, that help me to write the code fact and easier. but isn't appear to me

I would like to know, how to activate this sensitive suggestion box? and knowing that this visual studio 2010 installed successfully. even know that this sensitive box working in VB forms normally, but Visual C++ not.

thanks for advance