Destroy 3D text

Hi, I'am making a game thats there in the menu is a text whitch says that "there is no downloadable content installed". What i want to do is that if the person who downloaded the game and has no downloadable content yet installed this text appeares. But when the person downloaded and installed the downloadeble content the text will dissapear . How do i do that in scripting ?

Sorry for my bad english.

No downloadable content the text is in the main menu "No downloadable content installed" If Downloadable content is installed the text must not appear again.

You could use something like this in your OnGUI:

function OnGUI()
{
  if (!contentIsDownloaded)
  {
    GUI.Label(Rect(10,10,200,30), "There is no downloadable content installed");
    if (GUI.Button(Rect(10, 50, 200, 30), "Download content now!")
    {
      // Download your content
      DownloadAllContentYouNeed();
      contentIsDownloaded = true;
    }
  }
}

Hope that helps. You will probably have to check if the content is already downloaded when you start your game (look whether certain files exist, using PlayerPrefs, ...).

EDIT: I have read your question again and now think your main problem is checking whether the content is already downloaded. To help you with that you should tell us where your content is stored and what kind of content it is.