I have got troubles with Union command. autocad 2012

[s.shivaprem]

Hi!

I have got troubles with Union command.
I am trying to use union for 2 objects and I receive the following message

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Select objects: Specify opposite corner: 36 found

Select objects:

At least 2 solids, surfaces, or coplanar regions must be selected.

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[nestly2 · Accepted solution]

The fins are a Polar Array, which much be EXPLODEd back into individual solids before they may be UNIONed.

[s.shivaprem]

Thank you!
It works!!!!!