The DRF Referenced Is Not Valid
The geometric tolerance references a DRF that is not valid. This problem is probably caused by one of the following:
There was a change to the CAD model that caused one or more of the datum features that the DRF references to become invalid.
Features have been reordered in the GD&T Advisor Feature Tree such that the referenced DRF no longer precedes the feature that the geometric tolerance is applied to.
To repair this problem, you should first make sure that the Feature Tree is ordered such that the referenced DRF precedes the feature. If the referenced DRF is invalid, the best approach for repairing a geometric tolerance is to repair the invalid DRF that it references. A DRF is often invalid because it references an invalid feature (i.e., the feature is missing surface references), so any invalid DRFs and geometric tolerances in the model can usually be repaired by repairing the invalid features in the model. Thus, the best approach for repairing a model with invalid objects is to repair invalid objects in the following order:
1. Features
2. DRFs
3. Geometric Tolerances
You might also fix this problem by removing the invalid geometric tolerance from the feature through the following procedure:
1. Right-click on the feature in the Feature Tree and select Edit... from the context menu.
2. Specify the geometric tolerances in the dashboard as desired.
3. Click the Accept button in the dashboard.