To Delete All Versions of a File
To delete all versions of the current object:
1. Click File > Manage File > Delete All Versions. A Delete All Confirm message appears.
2. Click Yes to delete all versions of the current object.
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You cannot delete a part or subassembly that has been used in an assembly or drawing during the current working session until the assembly or drawing is deleted.
If the object is an instance, neither the instance nor the generic is deleted. If an object is a generic and you select it for deletion, only the generic is deleted.