Setup Zebra printer on Windows
Webshipper labels (and printers) are sold at Fragtlabels.nu and measures 102x192mm.
Open 'Control Panel' on your machine and go to 'View devices and printers'.
Find your Zebra printer and right-click on it.
Choose 'Printing preferences'.
Make sure the printing dimensions are set to 102x192 mm.
Save your changes and you are done :)
Please see this guide for configuring the print settings:
Fix labels being grainy or blurry when printed on a Zebra label printer