Object reference not set to an instance of an object

[betul]

Hi,I created a datalist in a master page and used this page in Default.aspx, when I open the browser it gives this error;Object reference not set to an instance of an object.The error belongs to;

			conn.Open();			adapter.Fill(d, "Categories");			menuList.DataSource = new DataView(d.Tables[0]);	  //this line 			menuList.DataBind();

When I remove masterpage and bind the datalist in Default.aspx.cs with the same code, it works perfect. However I don't want to bind it in each page again and again.. What might be the problem?Thanks.

[aspnetguy]

Please post the code for your master page and default page (including code behind).

[betul]

Thank you, I removed all the files and rewrote the code, finally it works.