FAQs & Troubleshooting FAQ Search Results QL-820NWB Not your product? Search by FAQ ID number Search Back to FAQs & Troubleshooting. 2 Results 1.faqp00000324_004 (Video) The message "Cassette not installed" is displayed on the print monitor screen. What should I do? 2.faqp00000324_002 The message "Cassette not installed" is displayed on the print monitor screen. What should I do? FAQs & Troubleshooting