Cause

In the parts database to be checked a part was found at which a unit group is defined for a property of the "Value with unit" field type. However, an invalid unit was specified for the property value of the part.

Solution

1. In the parts management mark the line with the message in the Messages tab and select the Go to popup menu item for this line.
   The respective part is marked in the tree view of the parts management.
2. Bring the tab Properties or User-defined properties to the foreground.
3. Enter a valid unit for the value of the affected property.
4. Click [Apply].
5. If required, start a new check run.
6. Close the parts management and perform a parts data synchronization.