Please check the following points:

• Make sure that you use paper that meets our specifications.
  To see what kind of paper you can use, click here.
  
  
• Change the paper to freshly unpacked paper.
  
  
• Make sure that the front cover is closed properly.
  
  
• Shake the toner cartridges gently.
  
  
• Wipe the scanner windows with a dry lint free soft cloth. 
  To see how to clean the inside of the printer, click here.
  
  
• The color calibration data stored in your printer may not be the latest one.
  Perform the color calibration and get the latest color calibration data.
  To see how to perform the color calibration and get the latest color calibration data, click here.