How to make Epson thermal printer print darker?

The Epson TM-T88III is a thermal printer so it does not use ink, it prints on special thermal paper only. Be sure you have the correct paper in the unit. If it is correct and the printer still does not print then you have a problem with the print head and the printer will need to go in for service.

1. for print cartridge2.for print media
3.for room temperature not adjust with printer needed .
4bad contact with print cartridge and the printer

The printer has some dipswitches under the panel on the bottom of the printer. Dipswitch 2-5 needs to be OFF and dipswitch 2-6 needs to be ON for darkest print. Default is medium. This printer is 180dpi so recommend using double size characters for darkest printing.

possible the ribbon is not the best in related to that especific labels, change ribbon.

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

Either the print head is failing or the batteries need replacing

Did you set it up using Epson's receipt printer drivers? If so, right click on it and choose properties. Under the PORT tab, check and make sure it is set for proper port (LPT1, COM1, USB, etc). If you make changes, click APPLY, then OK. Then Right click, PROPERTIES, Print test Page. If you can't get test page to print, your wasting your time sending codes to printer.
Let me know if you need more assistance.

using vb how can i change font size an epson tm88 prints

Either clean the print head nozzles or select a higher print quality and turn off High Speed mode.

try editing the photo.. more brightness, contrast etc etc.. see if it will also print brighter... if it still prints the same i guess its time to throw the printer back to epson