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enter image description here the add options are greyed out (in all tabs) I can't use them. Any help? BLENDER VERSION: 2.78

marked as duplicate by cegaton, p2or, JakeD, Mr Zak, David Jun 10 '17 at 19:25

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Check Use Nodes at the bottom of the Node Editor.

enter image description here

  1. Enable Use Nodes as Scott said if you want to add material nodes.
  2. Switch to Compositor nodes which would have a separate Use Nodes button by clicking the second item in the enum.
  3. You probably want to switch to Cycles at the top to have the "normal" nodes :-)

enter image description here

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