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Note: If you edit the original file from which the xref was created, the block in the current library will not change. You will need to recreate the xref.

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External References Panel

If you click on the External References button at the top of the Block palette you will see the External References panel at the bottom of the palette.

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Exploding XREFs: When an XREF has been bound to a drawing it becomes a block. Instances of that block in the drawing can be exploded so that you can edit the geometry directly in the drawing.