Cause: Windows is powering off the COM port to save energy. Fix:
| Driver Type | Interface | Exclusive Capability | Typical Use | |-------------|-----------|----------------------|--------------| | Epson APD (Advanced Printer Driver) | Serial, USB, Ethernet | Yes (locks port, raw mode) | Windows POS, OPOS | | Epson ESC/POS Driver (Virtual COM) | USB (CDC-ACM) | Conditional (can be shared) | Legacy apps | | Generic/Text Only | Any | No (Windows adds headers) | Not recommended | | OPOS / JavaPOS | Any (via APD) | Yes (direct IOCTL calls) | POS for .NET, Java | epson tm u220d driver exclusive
Exclusive choice: Epson APD + OPOS service running as a dedicated service. Cause: Windows is powering off the COM port to save energy
Cause: Wrong driver mode. You are using a Windows Generic driver, not the exclusive OPOS driver. Fix: Remove the printer from Windows "Printers & Scanners." Re-install using only the SetupPOS utility. Exclusive choice: Epson APD + OPOS service running
This is the definitive installation process for the Epson TM U220D driver exclusive on a modern Windows POS system.