MFC-7420 FAQs & Troubleshooting MFC-7420 Not your product? Sort by: Updated Date Popularity 4 Results 1. 06/18/2014 How can I improve poor print quality ? 2. 05/15/2013 How do I clean white or black spots on printed documents? 3. 05/09/2013 How can I improve the copy quality? 4. 05/09/2013 How do I clear vertical lines or streaks that appear in the copies I made? Copy FAQs & Troubleshooting