title: Why I can't load a user control to my toolbox in visual studio 2012 pro?
body: <p>Im going to the toolbox and doing right click then choose items then im going to the COM Components tab then browse and my file name wich in this case is LineGraph.dll I see this file on my hard disk I also did properties on the file and I see that the type is .DLL</p>
  
  <p>But when im trying to load/open it in the toobox im getting error: LineGraph.tlb could not be loaded.
  But the file is .dll where from this .tlb came ?</p>
  
  <p><img src="https://i.stack.imgur.com/hHBOb.jpg" alt="enter image description here"></p>