: This usually indicates a dirty print head. Clean it with an alcohol-soaked swab. You may also need to increase the Darkness/Density setting in the driver preferences.
: After installation, go to Printer Properties -> Preferences and set the default size to 4.00" x 6.00" for standard shipping labels. Troubleshooting Common Issues q108vprinter driver link
: During installation, select USB as the connection type (unless setting up via Bluetooth). : This usually indicates a dirty print head