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Freddy M.
Freddy M., Technician
Category: Printers
Satisfied Customers: 18409
Experience:  Years of experience
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Hi. I have used a Pixma MP640 for some time with great success,

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Hi. I have used a Pixma MP640 for some time with great success, both with Canon and other inks. This week an effect similar to solarization has appeared - the darkest tones are reversed to a pale blue and the general effect is muddy. The problem is not obvious on prints of low contrast. I am currently using windows XP and have today updated the printer drivers from Canon, but to no effect. I have tried both Ilford and Canon glossy papers and the results are very similar. Any ideas? Any help wouldl be greatly appreciated. Kind regards, Ted
Hello my name isXXXXX look forward to assisting and am very sorry to hear that you are having this problem.
Before we start I want to make sure you understand it is possible you will need to replace a part in order to fix this.
Customer: replied 4 years ago.

Hi Freddy M.


OK, assuming the part is availalbe. If its cost is too high, of course, I'd consider replacing the printer - a shame as it has worked well.



Unfortunately parts can sometimes be expensive tend, We need to troubleshoot first I just wanted to make sure you were aware of the possibility.
Hopefully you will not need to replace anything.

Let's try doing a manual cleaning of the machine and see if that helps at all.
If you have any trouble or get stuck at any point please let me know so I can help you.

Remove all the ink cartridges from the machine.
Then clean the contacts on the cartridges as well as inside the machine itself.
Do this with a small amount of warm water on a cotton swab until no ink comes off on the swab.
If any of the other cartridges are low, empty, leaking or bulging replace them.

Now once you have done all of that turn off the machine and unplug it for 70 seconds
Plug it back it and wait for the insert cartridges message
Insert the cartridges and check to see if the problem is still there.

If this did not work please come back and let me know by clicking on reply to expert so we can continue.
If it did work please don’t forget to leave a positive rating it is greatly appreciated.
Freddy M. and 2 other Printers Specialists are ready to help you
Customer: replied 4 years ago.



It worked perfectly, although the contacts had looked perfectly clean and nothing to speak of came off on the swabs (cotton-buds on this side of The Pond). Very many thanks. A lesson learned!


Kindest regards,



You're welcome and I hope you have a wonderful rest of your day.
Customer: replied 4 years ago.

Hi Freddy


I've received a "you have not responded" message (twice). As you can see, I have. Your advice was spot-on and I posted a big smiley for you. Thanks again - I should etch "RFM" on my brow!


Best regards,