“Driver is not digitally signed” – On Windows 10, reboot into Startup Settings > Disable driver signature enforcement (temporary fix), or install the signed version if available.
Printer prints garbage characters – You likely selected a generic driver. Reinstall using the exact “Have Disk” method above.
USB not detected – Try a different USB port and a short, high-quality cable (thermal printers are sensitive to cable length >3m).
Offline status – Open Services.msc, restart Print Spooler, then set printer to “Online” in Devices.
3. Install ESC/POS driver (recommended for full features)