Question about Zebra QL420 Thermal Printer

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Problem in printing with QL 420 Plus USB thermal printer


I have QL 420+ thermal printer. The printer driver was installed and through the driver i could print test page and my own contents. But even by using the CPCL commands, i cannot make the printer to print through my .net application. i wrote a simple application in (with backend coding in vb) but it doesn't print.


Please provide me some help in assist me in this regard.


Thanks and Best Regards,


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5 Suggested Answers

  • 2976 Answers

SOURCE: setup for zebra z4m plus

Make sure to select the proper printer when you send it to print. Also, make sure the printer is calibrated to the size labels you are using.

Posted on Feb 05, 2009

  • 17 Answers

SOURCE: Read and print .DAT files on labels

you must embed ZPL/CPCL or EPL command to your program.. or use Zebra Designer Pro then connect the .DAT file to it and design your sticker.. 

Posted on Mar 21, 2009

  • 53 Answers

SOURCE: Zebra LP2824 not printing

Sounds like you put your printer into line mode. Line mode prints code so you can see what is sent to the printer to look for possible mistakes in the code.

To switch from line mode back to page mode.

  1. Turn printer off.
  2. Press and hold the feed button down. And switch printer on.
  3. Release the feed button when the LED flashes red.
  4. When the LED flashes green, press down the feed button.
  5. When the LED flashes amber release the feed button.
  6. Try printing now that the printer is back in page mode which is used for print your labels; line mode prints the labels code.
  7. Do this fast or else it wont work if you are slow.

Posted on May 12, 2009

  • 35 Answers


The TLP2844 can print from any windows application providing the application can use a windows printer driver.
The page size oof the .pdf needs to be the same size as the physical label size.

Posted on Feb 16, 2010

  • 285 Answers

SOURCE: In Zebra 105sl Thermal Printer

try download other driver,, and try again.

Posted on Nov 25, 2010

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