MFC-640CW FAQs & Troubleshooting MFC-640CW Not your product? Sort by: Updated Date Popularity 3 Results 1. 19/05/2016 When I print, the pages are smudged with ink. What should I do? 2. 11/03/2016 One or more of my colours are not printing (blank). What can I do? 3. 17/09/2014 Why are my sent faxes always received with a black vertical line down the page? More FAQs Fax FAQs & Troubleshooting