error in Gridview

hello what is this error ? "An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. "

Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

I used this code in my web site and I don't use from datasource . "if (!IsPostBack) { InstalledFontCollection Fonts = new InstalledFontCollection(); GridView1.DataSource = Fonts.Families; GridView1.DataBind(); } " thank you .

From stackoverflow

• What type of data source did you use? If the GridView doesn't have a DataSourceControl to use for these actions then you have to create your own for paging and sorting.

• Since you are binding by code, the event asocciated with changing a page isn't supported by default.

  To support it you must code by yourself the PageIndexChanging event. Look that you have a parameter GridViewPageEventArgs that allows you to know wich page was selected.

  More information here, and a very deep article here.