Changed rolls of labels on Zebra GX 420T and now nothing prints

Extended two key means one of the buttons by the LCD are sticking and not releasing, you use the two key sequence to print a device configuration but if you hold in the buttons for too long r they are sticking that's when you get the extended two key error.

You must callibrate you media first.
The size of these labels are different frrom those that work correctly.
See in your manual how to callibrate media.

The new labels are probably not thermal labels. Test them by applying heat to the surface and see if they turn black. If they do not change, then they are thermal transfer labels and not direct thermal. Contact your label vendor and have them replaced.

you need to adjust the print head and perform a calibration.

here is the user manual:

http://tinyurl.com/4l3xghr

Click on this link or copy and paste the complete link into your browser.

If I could be of further assistance, let me know. If this helps or solves the issue, please rate it and give a testimonial for my response

Thanks, Joe

I’m happy to assist further over the phone at https://www.6ya.com/expert/joe_8b8c2cd6ce148309

Make sure the pause light is on and press calibrate. See if this calibration solves the problem. If not align the media sensors (top and bottom) to a position that is aligned with the least amount of preprinted data and calibrate again. Print configuration Power on while holding cancel key for 10 seconds. Use the config to help troubleshoot. Make sure the sensor type matches the media. Download user manual at zebra.com.

possible the ribbon is on the outher way.
The darkness is to low.

Make sure you are using thermal paper roll and not regular label roll.

If you put 2 rolls in, the labels will float around, since there is no way to keep each loose end in place.

just switch off the printer ,and then hold the green button power on the printer now and wait upto 4 bliknks of green led then remove the fingers.now printer will calibrate the label..

if still the problem exist .check the notch in the ribbon core.an adjust the spring tenson of rippon supply and take of roolers in printer

Warren
one side of the paper will be sensitive to heat and the other side won't be. If it is thermal paper run a pen without the actual ink part sticking out of the pen or use a key from your key ring in your pocket over the paper the friction should leave marks on the thermal side of the paper.
you may have the paper in with the non thermal side facing the heat printing part of the paper. Or you have the wrong paper.

http://www.microtrade.com.au/zebra-printer-ribbon-suits-tlp2824-plus-label-printer/?gclid=Cj0KEQiAuonGBRCaotXoycysvIMBEiQAcxV0nOLqC5Do2fiZih4Z19jw389fNmbkQXNwgUfYVzkqdSgaAhbc8P8HAQ

ld4028-10a or ld21084 may be the label ? not sure its 40 mm wide not 55 mm or 2.2 inch