The error occurs when loading objects if their PK value corresponds to the default value of the data type.
Example: The PK is of type Int and there is an object in the table that has the PK value 0. All other objects can be loaded (ReloadObject), but not this one, then the above-mentioned error message appears
This is a product defect (33258).
This will be fixed in a future release of the product. If you require this immediately corrected, please contact support for a hotfix referencing the defect ID 33258.