There is a report you can run based on role of Bad Emails. The report can be found in any area of the software via navigating to:
  1. Analysis > Reports
  2. Category: User Management > Email Management
  3. Select Bad/Missing E-mail
  4. Click Run
  5. From here you can search by Role such as Parent, Student etc, and Email type such as All, Invalid, Bad, Missing 
  6. Click Generate if you just want to run the results, View/Print PDF, View/Print Word, Export to Excel if you need to print or save the report externally