Do not suceed to print with usb-to-serial cable

The drivers are here:
https://download.epson-biz.com/modules/pos/index.php?page=prod&pcat=3&pid=22
Good Luck

Since you are using the USB-to-serial converter, you need to select the serial interface in the printer driver installation.

1. Uninstall the driver in Control Panel > Add or remove programs
2. Restart the computer
3. Install the printer driver again, this time select serial in the interface list
4. Set the properties for the serial port to 9600 for the data rate
5. Print a test page!

Bar codes are data intense transfers for any printer. This is not unusual.

Your printer is probably set to Off Line. You'll need to go to Start-Printers and Faxes, and in the new window right-click the Epson TM-T88III icon and from the popup menu select the Use Printer Online setting.
If this doesnt work check to see if the USB cable is loose both at the PC end and at the printer end. While you're at it, see if the printer shows any signs of life (any lights on, any messages on the LCD)? There just may be an issue of loose power cable, so you may want to check that also.

Please get it here : www.epson.co.id/epson/drivers/driver_download.htm
www.printcountry.com/drivers/EPSON_DRIVERS.asp
Jay lkg

Try setting both switch 1-7 and 1-8 to ON for 38400 baud, set switch 1-2 to OFF to give a 4k buffer, set switch 2-5 to OFF to release the busy buffer at 256 bytes, set switches 2-3 and 2-4 to ON & OFF for medium print density and OFF & ON for dark print density or OFF & OFF for normal print density.

Also remember that the thermal TM-T88III also prints faster when the print head is cooler and slower when it heats up. The print speed is adjusted automatically depending on the voltage applied and head temperature. So make sure your power supply is providing a steady 24VDC at full load and has enough capacity to provide a peak of 7.7A in full speed mode. If you are using the printer in high temp and humidity you might want to swap the unit out for a Star Printer which performs faster and uses the same protocol or use a cooling fan.

Also make sure you use a good quality paper and that the humidity is within range at 10 – 90% RH although the paper performance will be greatly diminished at higher humidity levels.


Specifications:

High-speed = Approx. 150 mm/s {5.9"/s} max.; 47.2 lps, max. (3.18 mm {1/8"} feed);
35.5 lps, max. (4.23 mm {1/6"} feed, at 24 V, 28°C {82°F}, density level 1).

Low-power: Approx. 16.5 lps (4.23 mm feed {1/6"}); 70 mm/s {2.76"/s}
Ladder bar code: Approx. 42 mm/s {approx. 1.7"/s}

High-speed mode: Mean: Approx. 1.8A Peak: Approximately 7.7A @24VDC
Low-power mode: Mean: Approx. 1.2A Peak: Approximately 6.6A @ 24VDC

Operating temp = 5 to 45°C {41 to 113°F}
Operating Humidity = 10% - 90% RH

I would like to say sorry to you I got my serial port mixed up with the parallel port. I have resolved the problem, it was a DIP switch change which needed to be set. If anybody can not get their computer to communicate with the printer then I would suggest they download the Epson Technical reference guide and read it thoroughly, but only use the guides for your method of connection which is dependent on your model of printer. I found that for a baud rate of 38400 DIP switch SW 1 numbers 7 & 8 should be switched to ON .I hope this helps some else.

Use the WIN XP driver. It works OK.

unistall the epson driver.
reboot your system.
connect and turn on the printer.
reinstall the driver, v3.02, selecting for create a serial port.
choose the right setting os serial interface.
after install, reboot your system.

it works to me.

Absolutely not. The Tranz 330 port is an RS232 serial port.