It prints unclear or not dark
By default, the printer is set to print at its fastest. Slowing this speed will result in a higher resolution. We suggest that you can increase the density/darkness and slow speed on your setting pages.
For Windows:
You may access these settings by going to your Control Panel -> Printers and Devices -> Right Click on OFFNOVA N-6140-> Printer Preferences -> Settings-> Page setup
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For Mac: Look for drop down menu under "Printer Features".
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For smartphone: