I am using ILLustrator CS and the brush tool is locked? Where is the option to unlock it?

Hi, I am using illustrator CS. I placed an Image to trace it. I finished the image. Deleted the layer with the photograph but now the brush is not working. The pencil is fine but the brush has this circle synbol as if saying that I can't use it.





Where can i unlock it?


I have switched from outline view to printview and nothing.





Thank you!I am using ILLustrator CS and the brush tool is locked? Where is the option to unlock it?
check which layer is selected, and if any are locked, then check brush palette options are turned on,





http://jura.wi.mit.edu/bio/graphics/illu…


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