I assume you are using SpaceClaim.
Please check geometry in SpaceClaim.
Select geometry in structure tree --> Use right click --> Select Check Geometry. (Or Tools - Fault Detection in DM)
The geometry should be error free to proceed.
If geometry has any errors, please modify/recreate geometry at those places.
Please go through help manual for more details
How to access Ansys Online Help Document
Guidelines on the Student Community
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