Validate Form Selections
You should always check your form selections the Form Types Configuration setting (Configuration > File menu > Form Types) after making changes in the Custom Reports utility.
When you make changes to your custom forms, you can potentially delete or rename a custom form selected in Form Setup. If you do, the original form is still selected. You need to select the form with the new name or another form.
R.O. Writer recommends test printing these forms after validating the form type selections. If a form that does not actually exist in the database is selected in Form Types, the following error appears when you try to print that form: