Sketch error crops up after creating a mirrored part related to first part

Folks,

     We have one part that when we use the "Insert/Mirror Part" command generates a sketch error in the mirrored part.  I can find which constraint is causing it in the original part, but really cannot figure out why that would happen since it is only copying the sketches and the error is NOT in the original partfile.  I have seen this before but has been awhile.

SW2010 SP4.0

TIA

Brian

     So thoughts or opinions then??

Thanks,

Brian

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