The print comes out with a shadow (looks like you are seeing double). I have done everything the book tells you to do. 1. Cleaned the print heads at least 5 x's. 2. Did a print test for the colors of ink. That was fine. 3. Did an printing alignment. alignment sample is printed the 600 and 1200dpi samples none of them match sample #0 I have tried to use the closest one but that does not change the quality of print.

Allen, that's very unusual. I've been using a workforce printer for years, and haven't ever seen anything like that.
What paper are you using, and what paper setting in your computer?
When you rand a nozzle test, were the nozzle lines even, or did some look kind of out of place? (a deflected nozzle will give that gosting effect, and "underhead cleaning" is the answer)

change the black ink cartage and try

Good for you Deborah but I already typed this one up.

1) With the machine turned on, park your print head like you are going to replace ink cartridges

2) Remove all the ink cartridges. Turn off the machine. Put a piece of tape across the felts of the ink cartridges keep the ink from drying.

3) To the left upper edge of the printer carriage there is a 3 inch long metal handle - lever. It is under a bit of tension from a stiff spring but lift it and rotate it toward the rear of the machine. this will release the printer head from the carriage. The printer head can be recognized by the 5 felts across the bottom. Lift and rotate the printer head toward the front of the machine. it will come out easily.

5) THE BOOK SAYS not to touch the printer head or contacts. I clean both with a Q-Tip dipped in rubbing alcohol. If the head is really filthy soak a paper towel with rubbing alcohol and gently blot the head on the towel. the ink will be absorbed by the fibers of the towel.

6) Once you have cleaned the print head, move the carriage all the way to the left and spend some time with Q-Tips and alcohol and clean as much ink off the top of the purge unit as you can reach.

7) CAREFULLY examine the clear plastic tape just below the carriage drive belt which is the brain of the carriage unit and tells the printer where it is. Use a clean Q-Tip to remove any ink or grease which might have gotten on the tape. If any foreign matter remains on the tape after you are done, the printer will not work properly again until you clean it. I know because I spent several hours working on an old HP and got ink on the tape. It would not work until I noticed the ink and cleaned it off. HP technical support does not have this as part of their knowledge base.

8) I put a drop of water and a drop of alcohol on the felts of the ink cartridges and the printer head when I reassemble everything to so as to "loosen everything up".

9) Run some test prints and see how everything works

10) Remember the simplest things to fix are quite often the things we overlook when searching for complicated answers.

Hi you are right its the print head only 1/2 of the black jets are working
keep cleaning but if that is not working look in your user book and you will see its very simple to replace the print head but not cheep.
if to go to www.amazon.co.uk and search Canon PIXMA MP830 print head you will see they have stock at £59.99
if this was useful please rate me
Ian

change cartridge
the print head of our cartridge is damaged 

Open the cover over the print head and *carefully* inspect the clear thin plastic strip that runs from left to right near the print head. If you see any lubricant (white grease) on this encoder strip, it needs to be cleaned off.
1. With the cover open and the print head in the center, unplug the power cord. This will allow you to gently move the print head left or right.
2. With a cotton swab wetted with rubbing alcohol, *gently* wipe the grease spots from the encoder strip. (Be VERY CAREFUL you don't dislodge the strip.) You may need to move the print head to the left or right to get all areas cleaned.
3. Let the alcohol dry off completely. With the area clear of cleaning tools, debris, and fingers, plug the power back in.
4. Try a test print.

my print head had to be replaced it was $112 so i will see if the printer expert was right.i didn't have to pay for this person to tell me ,i first took my print head to a cartridge refill place at wynnum,CARTRIGE WORLD and with his experience he could tell it was the print head that had to be replaced.

I have the same promblem, after changing th print head.
It priints black if I change the paper to photo paper.

You need to re-align the heads of your printer... go to printer properties - then printer preferences - click on maintenance ... now align those print problems... 

Try brand new genuine cartridges, if that does not work, it is your printer's print heads. Canon has these built into the printer as opposed to having them built into each new cartridge. Sometimes cleaning the heads a few times does not do much at all. On some occassions I have cleaned the print heads over 20 times and have succeeded eventually in getting it to print. Good luck.