Error when adding custom pipeline component

I'm getting the following error when I try to add a custom pipeline
component...
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You have selected an invalid pipeline component assembly. Please check
security settings for the assembly if you are loading it from an UNC path
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Anyone know what's wrong?

I've successfully added this component in the past, but recently added it to
a new solution and now it gets thsi error when I try to add it.

Thanks,
Jeff


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