DIAGNOSIS Windows is paired but lacks the correct driver to format the print job for a 4x6 label. It's sending a standard document print command the printer can't process.
FIX You must install the JADENS thermal printer driver on your Windows PC. 1. Download the "ZDesigner Driver" for 4-inch printers from the JADENS website or support portal. 2. Install it. 3. In Windows Settings > Bluetooth & devices > Printers & scanners, add a printer. 4. Select "The printer I want isn't listed," then choose "Add a local printer" and select the ZDesigner port you created. 5. When prompted for the driver, select "ZDesigner" and the correct model.
IF THAT DIDN'T WORK Your shipping software (like Pirate Ship) might be trying to print via a web browser. For browser-based apps, you must set the ZDesigner driver as your default Windows printer before printing.
HEADS UP Do not use the generic "Microsoft Print to PDF" or any standard document printer driver. It will pair but never print. The specific thermal driver is non-negotiable.