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Print problem grey or dull characters when black

Try going into Control Panel

--> Printers and Faxes

--> Right Click on the Printer ICON and select "Properties"

Look for a "Maintenance" or "Tools" Tab across the top click these to see it there is "Cleaning" or "Deep Cleaning" options

If you cannot see thesa try clicking on "Printing Preferences"
for "Maintenance" or "Tools"    IP