Carriage jam message

Ok guys I was struggling with the same issue for HP 3520, so I opened the cartridge access door and press down on a small black piece of plastic (that holds the carriage in place) once you press it there will be a slight click sound and thenn move the carriage to the right hand side.
Now close the lead and click ok the clear message.

You should be ok.

This method worked for my model.
You must have the power turned on otherwise it won't move.

Did you already try these steps?
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00243856&cc=us&lc=en&dlc=en&product=421139

If paper is jammed, a Paper jam message will appear on the control panel display.

Follow these steps to clear the jam:

1. Gently pull any jammed paper out of the output tray or sheet feeder.
   
   
2. If the paper is stuck inside, turn off the Epson Stylus CX.
   
   
3. Open the scanner, remove the jammed paper and torn pieces, close the scanner, and turn the Epson Stylus CX back on.
   
   Note: Be sure to check the far left of the carriage area when checking for jammed paper. Paper that is jammed there may be hidden from view.

If paper jams inside the Automatic Document Feeder, clear the jam as follows:

1. Open the Automatic Document Feeder cover and remove any jammed paper.
   
   
   
   
2. If necessary, lift the document cover and remove any paper that has jammed inside.
   
   
   
   
3. Press OK to clear any messages on the display screen.

If paper is jammed, a Paper jam message will appear on the control panel display.

Follow these steps to clear the jam:

1. Gently pull any jammed paper out of the output tray or sheet feeder.
   
   
2. If the paper is stuck inside, turn off the Epson Stylus CX.
   
   
3. Open the scanner, remove the jammed paper and torn pieces, close the scanner, and turn the Epson Stylus CX back on.
   
   Note: Be sure to check the far left of the carriage area when checking for jammed paper. Paper that is jammed there may be hidden from view.

If paper jams inside the Automatic Document Feeder, clear the jam as follows:

1. Open the Automatic Document Feeder cover and remove any jammed paper.
   
   
   
   
2. If necessary, lift the document cover and remove any paper that has jammed inside.
   
   
   
   
3. Press OK to clear any messages on the display screen.

The carriage assembly is what the ink cartridges moves on. The silver bar that runs through the cartridge holder must be oiled. Put two or three drops of thin oil oun iether sides of the cartridge holder. This should clear the "carriage error"



Good Luck

I think the message is instructions, as in
(1) open door (2) clear carriage jam (3) press enter
So there is something internal to the printer that makes it think it has a carriage jam, piece of paper under a sensor, dirty or stuck sensor.
If you can't find it using a bright light, try canned air.

HP Officejet 7200, 7300, and 7400 Series - 'Paper Jam: Clear jam, and then press Enter' Message Displays on the Control Panel Display
Issue
During printing, the paper becomes stuck in the all-in-one and the error message 'Paper Jam: Clear jam, and then press Enter' displays on the control panel display.
Solution
Use the following instructions to clear a paper jam from the product:
Step one: Check for and remove any loose paper from the In tray
Do not try to remove jammed paper from the In tray. First remove any loose paper from the In tray to avoid worsening the jam.
CAUTION: Always try to remove jammed paper from the back of the printer first to avoid mechanical damage.
Step two: Clear the jam from the back of the printer
Follow these instructions to clear jammed paper from the back of the product. If the product is equipped with a two-sided printing accessory, skip to that section.
Remove the rear access door to clear the paper jam

1. Remove the rear access door by pressing the buttons on the side of the door and pulling it toward you.
Figure 1: Removing the rear access door
Rear access door
2. Gently pull the jammed paper out of the rollers.
WARNING: If the paper tears while removing it from the rollers, check the rollers and wheels for torn pieces of paper that might remain inside the product. If all the pieces of paper are not removed from the product, more paper jams might occur.
3. Replace the rear access door. Gently push the door into the all-in-one until it snaps firmly into place.

Remove the two-sided printing accessory to clear the paper jam

1. Remove the two-sided printing accessory by pressing in the buttons on the sides and then pulling the accessory toward you.
Figure 2: Removing the two-sided printing accessory
2. Gently remove any jammed paper.
WARNING: If the paper tears while removing it from the rollers, check the rollers and wheels for torn pieces of paper that might remain inside the accessory. If all the pieces of paper are not removed from the accessory, more paper jams might occur.
3. Press the button on top of the two-sided printing accessory to open the door.
Figure 3: Opening the two-sided printing accessory door
4. Gently pull the jammed paper out of the rollers.
5. Close the accessory door.
6. Reinstall the two-sided printing accessory.

Step three: Clear the jam from the automatic document feeder (ADF)

1. Remove the document feeder tray from the product by gently pulling it.
2. Lift the cover of the automatic document feeder by pulling it outward.
Figure 4: Lifting the cover of the automatic document feeder
Automatic document feeder (ADF) door
3. Gently pull the jammed paper out of the rollers.
WARNING: In the rare occurrence of a severe paper jam, you might need to remove the face plate from the front of the automatic document feeder and lift the pick assembly to remove torn pieces of paper from deep inside the automatic document feeder.
4. Close the cover of the automatic document feeder, and then reattach the document feeder tray.

Step four: Verify that the print carriage can move freely
Follow these steps to try to move the print carriage.
CAUTION: Do not force the print carriage to move if it is out of plain view or feels stuck. Forcing it may damage the printer.

1. With the product turned on, open the print cartridge access door. The print carriage might try to move into the access area. If so, allow it to move to that position.
2. Without turning off the product, unplug the power cord from the back of the product. Unplug the power cord from the power source. The power cord must be unplugged to allow the parts to be moved by hand and to reset the paper feed mechanism, without the risk of an electrical shock.
3. Looking in through either the print cartridge access door or the output paper tray, make sure the print cartridges are locked into the carriage and have not come loose. Also, make sure that there are no obstructions under or around the carriage to block it from moving.
4. Make sure the print carriage can move freely across the width of the product by gently pushing the carriage to the left and then to the right. Clear any obstructions found.
You may have to reach through the output paper tray to access the print carriage.
5. Close the print cartridge access door and plug the power cord back to the back of the product. Plug the power cord into the power source.
6. Press the On button to turn on the product.

Step five: Reload and test the printer
After you have removed the jammed paper, make sure the product is still functioning properly.

1. Reload the product with plain paper.
2. Peform a self-test by pressing and holding the RESUME button on the control panel until the product begins printing. A test page prints.

Step six: Service the printer
If you have completed all the steps listed above and are still experiencing a problem, service the product.

Still gotta be some paper in there. Be brave and pull it apart

I was able to run run a piece of photo paper through a couple of times and printer now seems to be working again. The theory was that running a heavy piece of paper through might help clear little piece of paper that was not visible. The photo paper is less likely to tear if it gets jammed too.

I have an Hp Officejet 5110. I have an error message saying "Open door,clear carriage jam, then press enter". But where is its door? How can I clear the carriage jam?

I tried pressing the # & 6 at the same time, but the error message still there.