Run a self test from the printer to eliminate your software, driver, and PC.
Run a cleaning cycle
Make sure that your cards are within spec
Try different cards
Manually clean the rollers
Make sure that your card size is selected properly in the driver (CR-79 or CR80)
Update the printer driver and firmware to the latest on Fargo’s website
Plug the printer directly into a wall socket as in our experience surge protectors can cause different issues with badge printers.