I have a CX6400 and recently had a paper jam in which too much paper tried to go through. I couldn't eject it so I pulled it gently from the top. Now the printer will not recognized that black ink is in and it only prints color or blank pages. Do I need to buy a new printer?

The simplest thing would be to try unplugging the printer from the power source. Let it rest for 5 - 10 minutes then plug back in to the power supply and see if that resolves the problem.

If not you are going to need to do a thorugh inspection to verify that all paper remnants have been removed.

The following is for the MP600:

Issue: ERROR LCD: The paper is jammed. Clear the paper and press [OK].
Solution: Removing paper jams MP600


Removing Obstructions or Jammed Paper If [Paper output slot - The paper is jammed. Clear the paper and press OK] appears on the LCD, follow this procedure to clear the paper jam Clearing paper jams from the auto sheet feeder (ASF) or paper output slot
Clearing paper jams inside the printer
Clearing credit card-sized or 4" x 6" paper jammed inside the printer

ASF / Paper Output Slot

1. Turn off the printer.
   
   
2. Remove paper from the ASF.
   
   
3. Gently pull the jammed paper out.
   
4. 1. If paper is visible from the ASF, use both hands to pull the paper out slowly.
      
   2. If paper is visible from the paper output slot, use both hands to pull the paper out slowly.
      
      
      The above illustration shows a PIXMA MP500.
      
      
5. If the paper tears and a piece of that remains inside the printer, open the scanning unit (printer cover) and remove the paper from inside the printer.
   
   Note:
   Be careful not to touch the components inside the printer.
   
   
   
6. Turn on the printer and confirm that the Alarm light is off.
   (If the jammed paper remains in the printer, the paper may be automatically ejected.)
   
   
7. Load paper back into the ASF.
   
   
8. Press to clear the message and continue printing. If you are printing from an application software, follow the instructions displayed on your computer.
   

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Paper jams inside the printer

1. Turn off the printer and disconnect the power cord and USB cable.
   
   
2. Remove the jammed paper slowly using the following procedure.
   
3. 1. Open the rear cover to check if the paper is jammed.
      
      
      
   2. Pull out the cassette and check if the paper is jammed inside the cassette area.
      
      
      
   3. Stand the printer with the left side down, holding the document cover.
      
   4. Press the tabs together and pull the green cover toward you.
      
   5. Check if the paper is jammed.
      (If you were not doing Duplex printing, you do not have to follow this procedure.)
      
      
      
      
   6. Close the green cover and place the printer back to a normal position.
      
4. Reconnect the power cord and power on the printer. Confirm the Alarm light is off.
   
   
5. Load paper back into the ASF or cassette.
   
   
6. Press to clear the message and continue printing. If you are printing from an application software, follow the instructions displayed on your computer.
   

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Clearing credit card-sized paper jammed inside the printer
Credit card-sized and 4" x 6" sized paper must be loaded properly. If this media is not loaded properly, it will feed into the printer and will not exit. Credit card-sized paper should only be loaded in the ASF and in portrait orientation. 4" x 6" sized paper can be loaded in the ASF or cassette. But must be loaded portrait orientation.
If credit card-sized paper was loaded in landscape orientation in the ASF and did not eject (exit), please follow this procedure.

1. Turn off the printer.
   
   
2. Load the same paper type that is jammed inside the printer in portrait orientation.
   
   
   
   
3. Power on the printer.
   The paper stock in the ASF will automatically feed the jammed paper from the printer.
   
   
4. To resume printing, load the paper in portrait orientation.

If 4" x 6" sized paper was loaded in landscape orientation in the cassette and did not eject (exit), please follow this procedure.

1. Turn off the printer.
   
   
2. Open the rear cover.
   
   
3. Fold in four a piece of letter-sized plain paper.
   
   
4. Push in the folded paper until it hits the jammed paper.
   
   
   
   
5. If the jammed paper is visible from inside the printer area, pull it out and proceed to step 7.
   
   
6. If the jammed paper cannot be pulled out, push in the folder paper from the rear so the jammed paper is in between the feed rollers.
   
   
7. Pull out the folded paper and close the rear cover.
   
   
8. Power on the printer and confirm that the Alarm light is off.
   The jammed paper should automatically eject.
   
   
9. To resume printing, load the paper in portrait orientation.

Trust this is helpful.

Try this solution: Check for paper jams when the "Error" LED lights red. Open and close the front cover. The paper may automatically be ejected from the printer. Gently pull any remaining jammed paper straight out. Open the front cover. Pull the toner cartridge out. Pull out any internal paper jams.

If the paper is jammed inside the machine follow these steps:
1. Open the front cover and pull the toner cartridge out, lightly pushing it down.
2. Remove the jammed paper by gently pulling it straight out.
3. After removing the jammed paper, make sure there is no additional paper in the paper path.
4. Insert the toner cartridge and close the front cover.

If the paper is jammed in exit are follow these steps:
1. Open and close the front cover. The jammed paper is automatically ejected from the machine.
2. Gently pull the paper out of the output tray.
- If you do not see the jammed paper or if there is any resistance when you pull, stop and go to the next step.
3. Open the rear cover.
4. Carefully remove the paper by pulling in the direction.
- If the paper tears, make sure that all of the paper fragments are removed from the printer.
5. Close the rear cover. Printing automatically resumes.

Seems like the rollers are either dirty, or worn out. Probably the latter.
• “Paper jams” on page 68
• “Paper or specialty media misfeeds” on page 68
• “Printer does not feed paper, envelopes, or specialty media” on page 69
• “Banner paper jams” on page 69
Paper jams
Is the jam in the paper
support?
1 Press to turn off the printer.
2 Firmly grasp the paper, and gently pull it out.
3 Press to turn the printer back on.
Is the jam in the printer? To automatically eject the paper:
1 Press to turn off the printer.
2 Press again to turn the printer back on.
The paper automatically ejects from the printer.
To manually remove the paper:
1 Press to turn off the printer.
2 Firmly grasp the paper, and gently pull it out.
3 Press to turn the printer back on.
Paper or specialty media misfeeds
If paper or specialty media misfeeds or skews, or if multiple sheets feed or stick together, try the following solutions.
Check paper
condition
Use only new, unwrinkled paper.
Check paper loading • Load a smaller amount of paper into the printer.
• Load paper with the print side facing you. (If you are not sure which side is the printable
side, see the instructions that came with the paper.)
See “Loading various paper types” on page 21 for information about:
• Maximum loading amounts per paper type
• Specific loading instructions for supported paper and specialty media
Troubleshooting
68
Remove each page as
it is printed
Remove each page as it exits, and let it dry completely before stacking.
Adjust the paper
guides
Adjust the paper guides:
• When using media less than 8.5 inches wide
• To rest against the edges of the paper or media, making sure it does not buckle

Firts remove the back panel by turning the large knowb in the center. Then if more than 2 pages are stuck inside "gently" pull on all the sheets except the top and bottom ones. They should pull out with moderate resistance. Once thos sheets are ou do the same thing with the remaining two sheets.
NOTE: when a printer is powered on with paper already in the paper path it will usually try to eject them by turning its rollers.
NOTE: some older HP DeskJets when you press the paper feed button (with paper already in printer) it will move the paper in one direction and when you press again it will move the paper in the opposite direction.

OK unscrew it

You can access Canon online support info here. Enter paper jam as a search, then choose #4 to remove the obstruction.
Also see this:
Issue: Paper is jammed inside the printer
Solution: Removing paper jams MP600

Removing Obstructions or Jammed Paper If [Paper output slot - The paper is jammed. Clear the paper and press OK] appears on the LCD, follow this procedure to clear the paper jam Clearing paper jams from the auto sheet feeder (ASF) or paper output slot
Clearing paper jams inside the printer
Clearing credit card-sized or 4" x 6" paper jammed inside the printer

ASF / Paper Output Slot

1. Turn off the printer.
   
   
2. Remove paper from the ASF.
   
   
3. Gently pull the jammed paper out.
   
4. 1. If paper is visible from the ASF, use both hands to pull the paper out slowly.
      
   2. If paper is visible from the paper output slot, use both hands to pull the paper out slowly.
      
      
      The above illustration shows a PIXMA MP500.
      
      
5. If the paper tears and a piece of that remains inside the printer, open the scanning unit (printer cover) and remove the paper from inside the printer.
   
   Note:
   Be careful not to touch the components inside the printer.
   
   
   
6. Turn on the printer and confirm that the Alarm light is off.
   (If the jammed paper remains in the printer, the paper may be automatically ejected.)
   
   
7. Load paper back into the ASF.
   
   
8. Press <OK> to clear the message and continue printing. If you are printing from an application software, follow the instructions displayed on your computer.
   

Top
Paper jams inside the printer

1. Turn off the printer and disconnect the power cord and USB cable.
   
   
2. Remove the jammed paper slowly using the following procedure.
   
3. 1. Open the rear cover to check if the paper is jammed.
      
      
      
   2. Pull out the cassette and check if the paper is jammed inside the cassette area.
      
      
      
   3. Stand the printer with the left side down, holding the document cover.
      
   4. Press the tabs together and pull the green cover toward you.
      
   5. Check if the paper is jammed.
      (If you were not doing Duplex printing, you do not have to follow this procedure.)
      
      
      
      
   6. Close the green cover and place the printer back to a normal position.
      
4. Reconnect the power cord and power on the printer. Confirm the Alarm light is off.
   
   
5. Load paper back into the ASF or cassette.
   
   
6. Press <OK> to clear the message and continue printing. If you are printing from an application software, follow the instructions displayed on your computer.
   

Top

Clearing credit card-sized paper jammed inside the printer
Credit card-sized and 4" x 6" sized paper must be loaded properly. If this media is not loaded properly, it will feed into the printer and will not exit. Credit card-sized paper should only be loaded in the ASF and in portrait orientation. 4" x 6" sized paper can be loaded in the ASF or cassette. But must be loaded portrait orientation.
If credit card-sized paper was loaded in landscape orientation in the ASF and did not eject (exit), please follow this procedure.

1. Turn off the printer.
   
   
2. Load the same paper type that is jammed inside the printer in portrait orientation.
   
   
   
   
3. Power on the printer.
   The paper stock in the ASF will automatically feed the jammed paper from the printer.
   
   
4. To resume printing, load the paper in portrait orientation.

If 4" x 6" sized paper was loaded in landscape orientation in the cassette and did not eject (exit), please follow this procedure.

1. Turn off the printer.
   
   
2. Open the rear cover.
   
   
3. Fold in four a piece of letter-sized plain paper.
   
   
4. Push in the folded paper until it hits the jammed paper.
   
   
   
   
5. If the jammed paper is visible from inside the printer area, pull it out and proceed to step 7.
   
   
6. If the jammed paper cannot be pulled out, push in the folder paper from the rear so the jammed paper is in between the feed rollers.
   
   
7. Pull out the folded paper and close the rear cover.
   
   
8. Power on the printer and confirm that the Alarm light is off.
   The jammed paper should automatically eject.
   
   
9. To resume printing, load the paper in portrait orientation.

I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
If I've managed to answer your question or solve a problem, please take just a moment to rate this post....thanks!

There is still a small piece of paper jammed in the machine. It should be in the area where the jam occurred.

Hi Jocase, there is most likely a foreign object in the paper path of your machine. Often tipping it on it's back will dislodge the offender, but not always. Take an A4 sheet of thick card (the back card off an A4 refill pad is good for this) and push it backward through the paper path. Start where the paper normaly comes out and feed the card backward throught hte exit rollers, and on toward the main feed rollers. Don't go too far to the right side (wear the head "parks") as the paper sensor could get broken off. Persuade the card through the rollers and gently tease it in in out. Tip the machine on its back again so anything dislodged is encourage to come out. Work the card in and out GENTLY taking care not to exert too much force. If nothing falls out, you may have to dismatle the machine to get to the ASF to manually remove the oblect. If you intend to dismantle the machine, get a manual from http://TheServiceManualShop.com to make sure you do it right without breaking anything.