Support.

Instructions on how to load media into the Zebra ZD420 desktop printer

1. The media status indicator will display red when media is exhausted
2. Open the printer
3. Remove the empty core from the core holder
4. Remove the outside wrap from the new media role to prevent contamination
5. Place the supply media in the role holder
6. Pull the end of the media out of the front of the printer
7. Verify the media sensor is in the correct location for your media
8. Press the media down under the media guides
9. Close the printer

Source: “ZD420C DESKTOP.” Zebra, https://www.zebra.com/us/en/support-downloads/printers/desktop/zd420c.html#knowledgearticlesear