What is E4 on Canon PIXMA and Other error codes

E4 is Error Code that explain about ink is empty.

E2-2 = No paper (ASF)
E3-3 = Paper jam
E4 = No ink
E5-5 = The ink cartridges are not installed or a non-supported ink cartridge is installed, or the ink cartridges are not installed properly
E8 = Waste ink absorber full, or platen waste ink absorber full
E9 = The connected digital camera / video camera does not support Camera Direct Printing

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