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Pixma MX439 Mode l#K10375 - Printing Problem


For a reason(s) I have not been able to identify, although the printer is receiving wi-fi, bluetooth and power, I keep getting an on-screen message on my computer  identifying a "computer/printer communication problem  (and a blank screen on the printer) when I try to print.  However, if I pull and then replace the power plug the printer starts to print without a problem - until the next print job, when I have to go through the "plug action" all over again. 


I apologise if there's a perfectly straightfoward reason for this problem that I've missed, but any helpful suggestion(s) would be much appreciated.


This may help:
It's a you tube video that shows how to carry out a Canon Printer Hard Reset - might not work for all printers though and do at your own risk. Did it to my MG5650 hoping it would rectify my own problem. It seemed to do the same thing as the video shows and printer still works (did not fix my problem though:(


Hi "Bazzer":


Thanks so much for your suggestion to "cure" my (Error Support Code: 300) problem. *


In fact  since posting my question I found what I hoped would be the solution on  The suggested solution started by saying "This (sic: problem) normally happens on a Mac".  I tried the suggestion, which in effect involved deleting the offending printer from my printer list and then re-adding it.  After doing this the printer worked fine, and I thought this action had in fact solved my problem.  Unfortunately, I later found that having shut down and then re-started my Mac, I had the same problem again and had to (literally) pull the plug on the printer and plug it straight back in again. What a pain........


** Just have to add that in fact before submitting my question to the Canon Community I had run through the hard set, alignment, cleaning, etc... options -  with no joy.

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