About Regeneration Failures
When a model is regenerated, the model is recreated feature by feature, in the order in which each feature was created, and according to the hierarchy of the parent-child relationship between features. Regeneration can fail for reasons such as the following:
Bad geometry
Broken parent-child relationships
Missing or invalid references
Missing components of an assembly
When a feature fails to regenerate, the system creates a failed feature. You can perform the following operations on a model that contains a failed feature:
Search for a failed feature
Modify other parts of the model
Fix the failure later
Mirror the geometry of a model with failed features
Save a model that has failed features
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Models saved with failures cannot be opened in versions of Pro/ENGINEER earlier than Wildfire 5.0.
In some cases, you can undo the changes that caused the failure. Undoing the changes cancels the regeneration. When you cannot or choose not to undo the changes, the regeneration is completed despite the failure. You can investigate the failed items in the Regeneration Manager. The failed status of the feature is removed when the feature is suppressed.