If it ever happens that you see QZ Tray Invalid Signature error message on your screen, try to follow these simple steps! 🔎
As a first thing, verify if your Antivirus is active, if so, disable it to proceed with the setup.
Check also if your Carriers have printer options set on ZPL / Zebra.
Then Uninstall and Install QZ Tray again by clicking on Print > Download QZ Tray
Click here to learn how to install QZ Tray on Windows:
Click here to learn how to install QZ Tray on Mac:
For more information about ZPL printing take a look at the guide below:
If nothing above seems to work, try to also:
Clear your browser cache multiple times
Access from Google Chrome Incognito mode
Update the browser you are using
Change browser
Use Printnode instead