To Unfreeze a Surface
1. Select one or more frozen surfaces or components.
2. Click Constrain > Freezing > Un-Freeze. Alternatively, right-click and click Un-Freeze. The selected surface is unfrozen and the icon   representing a frozen surface is removed from the surface. If you selected components, the surfaces in the components are unfrozen and the icon representing a frozen surface is removed from the surfaces.
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When you move the pointer over , Import DataDoctor displays a message indicating why the surface is frozen. If a surface is frozen because it is a trimmed surface with more than four distinct boundaries, it cannot be unfrozen without modification. If such a trimmed surface is selected, the Un-Freeze option is not available.
If multiple surfaces are selected for Un-Freeze and some of them cannot be unfrozen because they have more than four boundaries, the surfaces that cannot be unfrozen remain frozen, and all others are unfrozen.