I have the below mentioned printer a

you'd like to have it certified-tech serviced!

check between the rollers there will be small bits of paper jammed in that is the reason.

Double check all doors/ rollers for small pieces of paper stuck in the rollers. Sometimes just opening the door in question and closing will reset the paper jam sensors. Paper jams can be smaller than your pinky finger nail. So double check,

Comment if it still isn't working.

Regular paper, envelopes, or specialty media may get stuck or jammed in the printer. Follow the instructions below to find and remove jammed paper (or other media) from the printer. If the HP All-in-One has a paper jam, first check the rear door. If the jammed paper is not in the rear rollers, check the front door.

Step one: Check for and remove any paper stuck in the paper In tray

1. Remove all loose paper from the paper In tray.
2. Press the RESUME button.
   
   • If the paper jam is cleared, skip to Step Four
     
   • If the paper is still jammed, continue on to the next step below.

If more than one sheet is stuck in the printer, remove the paper, one sheet at a time by taking hold of a sheet in the middle of the stack and, with both hands and firm, even pressure, pull the sheet towards you. Usually, removing one or two sheets from the middle of the stack will release the pressure and the rest of the stack can be removed.

After removing the paper, check to make sure no scraps of paper are stuck in the printer.

• If the paper jam is cleared, skip to Step Four.
• If the paper is still jammed, continue on to the next section.
  
  

Step two: Clearing a paper jam from the back of the printer

If the paper jam is not accessible from the In tray, follow the instructions below to clear the paper from the back of the printer.

1. Unplug the HP All-in-One.
2. Press in the tab on the left side of the rear door to release the door. Remove the door by pulling it away from the HP All-in-One. Figure 1: Removing the rear door
   
   

1. Gently pull the paper out of the rollers.
   CAUTION:If the paper tears when removing it from the rollers, check the rollers and wheels for torn pieces of paper that might be remaining inside the device. If all of the pieces of paper are not removed from the HP All-in-One, more paper jams are likely to occur.
2. Replace the rear door. Gently push the door forward until it snaps into place.
3. Press Cancel to continue the current job.
   
   • If the paper jam is cleared, skip to Step Four
     
   • If the paper is still jammed, continue on to the next section.
     
     

Step three: Lift the front cover and slowly remove any jammed paper

1. Unplug the power cable.
2. If necessary, pull the input tray down to open it. Then, lower the print cartridge door. Figure 2: Lowering the print cartridge door
   
   

1. Gently pull the paper out of the rollers.
   CAUTION:If the paper tears when while removing it from the rollers, check the rollers and wheels for torn pieces of paper that might be remaining inside the device. If all the pieces of paper are not removed from the HP All-in-One, more paper jams are likely to occur.
2. Close the print cartridge door.
   Figure 3: Closing the print cartridge door
   

1. Plug the power cable into the HP All-in-One.
2. Turn the power on.
3. Press Start Copy Black or Start Copy Color to continue the current job.

Step four: Verify the print cartridge carriage can move freely

1. Unplug the power cable.
2. Check to see if the print cartridge carriage can move freely from one side of the printer to the other. If the carriage is to the right and out of plain view, skip to Step Five. Do not try to force it to move if it is hung up on something. [img src="http://h10025.www1.hp.com/ewfrf-JAVA/Image/common/note.png" alt="">
   NOTE:Be careful not to force the print cartridge carriage. If the carriage is stuck, forcing it to move will damage the printer.
   
   • If the carriage does not move, continue with the next step below.

Remove the print cartridges.

Step five: Reload and test the printer

Once the jammed paper is removed, verify that the printer is still functioning properly.

1. Reload the printer with plain paper.
2. Perform a self-test by pressing and holding the Resume button until the printer starts printing. A test page should print.

NOTE:Do not put more than 35 sheets of plain paper in the document feeder tray.

Gently move the print cartridge to the far right of the printer.

Remove the paper from the paper In tray, but do not remove the drawer.

Remove the rear access door.

With your fingers, rotate the rollers "up" three full rotations.

Push the rear access door back into the printer until it snaps firmly into place.

Replace the print cartridges.

Plug the power cable into the HP All-in-One.

Turn the power on.

Step six: Service the printer

Perform all the steps mentioned above. If the problem continues, service the printer.
Cause Paper jams can be caused by several factors. Follow these guidelines to prevent further paper jams.

• Insert paper into the paper tray only until it meets resistance. Do not push it farther in.
• Make sure that the paper is flat in the paper tray and that the guide is adjusted to the width of the paper.
• Do not add paper while the product is printing.
• Remove printed pages frequently.
• Do not use paper that is too thin, too slick, or that stretches.
• Do not use torn or creased paper. Used paper might cause jams.
• Make sure that the rear access door is securely fastened.

what is the error ?
does it says Paper jam, Open the print cover and remove paper jam..

If this the error repeating then make sure,

1. u r not overfilling the paper tray
2. put the printer on a hard surface (not on a half out surface)
3. from now on be gentle with the paper tray.
4. unplug the printer everytime u r done or atleast overnight.

thanks

After an overnight shutdown the problem was gone.

The print carriage may get stuck on either side or in the middle of the printer. The Carriage Jam: Open Door, clear carriage jam, and then press OK to continue error message may display on the front panel of the all-in-one.

Solution
The print carriage is the device which contains the print head and moves left to right during printing.
Figure 1: Carriage Assembly

To resolve this issue, follow the steps below in the order presented.

Step one: Print a Self Test

Follow the steps below:
1. Press the Setup button.
2. Select Print Report and press OK .
3. The self-test page should print. If it prints a test page, there is no need to follow the remaining steps, as the error message may be false. Make sure the printer now prints from the computer (if installed on one). If it does not print, proceed to the step two.

Step two: Clear the paper path

Follow the steps below to clear the printer of any jammed paper and reset the printer.
1. Leave the printer on and then disconnect the power cable and the USB or Ethernet cable from the back of the printer. Do not reconnect them until instructed to later.

NOTE: Make sure the printer is on before disconnecting the power cord. Failure to disconnect the power cord from the rear of the unit can cause damage when removing jammed paper.

2. Open the top access door.

Figure 2: Opening the top access door

3. Make note of where the carriage is stuck and look for jammed paper. A paper jam can cause the error message and the carriage stall. Some paper may be jammed in different locations than those shown in the photos below.

Figure 3: Paper jammed on the left side

Figure 4: Top view of paper jammed on the left side

Figure 5: Paper jammed on the right side

Figure 6: Top view of paper jammed on the right side

NOTE: Do not use any tools or other devices to remove jammed paper. Always use caution when removing jammed paper from inside the unit.

If the carriage is stuck on the right side:
a. Check for any paper or object that may be restricting the carriage.
b. Move carriage all the way to the left side.
c. Check the paper path all the way to the right side and remove any paper still in the printer.

If the carriage is stuck on the left side:
d. Check for any paper or object that may be restricting the carriage.
e. Move carriage all the way to the right side.
f. Check the paper path all the way to the left side and remove any paper still in the printer.

If the carriage is stuck in the middle:
g. Check for any paper or object that may be restricting the carriage.
h. Move carriage all the way to the left side.
i. Check the paper path all the way to the right side and remove any paper still in the printer.
j. Move carriage all the way to the right side.
k. Check the paper path all the way to the left side and remove any paper still in the printer.
4. Remove the rear access door or duplexer (if installed) from the back of the printer.
5. Check for and remove any paper still in the printer.
6. Replace the rear access door, and close the top access door.
7. Reconnect only the power cable. If the printer does not automatically turn on, press the Power button.

NOTE: The printer may go through a warm-up period of up to two minutes. Lights may flash and the carriage may move. Wait until this warm-up period is complete before going to the next step.

8. If the Power light is on steady, print a self-test page as done in Step one.

If the Power light is not on steady and the carriage is still in a stalled position, proceed to the next step.

Step three: Plug the printer directly into a wall outlet

Verify that the printer is properly connected to a suitable power source by following the instructions below.
1. Verify that the computer and the printer have a three-prong power plug.
2. Remove the printer cable from any power strips or surge suppressors, and plug it directly into a grounded (three-prong) wall outlet.
3. Try the print job again to see if this step resolved the issue.

NOTE: If the printer prints when plugged directly into a wall outlet while disconnected from any power strips or surge suppressors, the power strip or surge suppressor may not be allowing sufficient voltage to reach the product.

4. If this did not resolve the issue, proceed to the next step.

Step four: Service the product

If you have completed all of the steps listed above and are still experiencing a problem, service your product.hope this helps

Manual Feed Command.
1. Press the Job Cancel button to cancel the print job. Delete the print
job in the print queue on the computer. You can quickly access the print queue by double clicking the Printer icon in the task
tray or dock.

2. Turn the printer power switch OFF on the right side of the printer.
Check that the front cover is closed.

3. Turn the printer power switch ON while holding down the GO button
until the Toner, Drum, and Paper LEDs are lit.

4. Release the GO button. All LEDs will be off.

5. Press the GO button 8 times. The green Status LED will flash briefly
while the printer is reset. After the printer is reset the Status LED
will be lit green.

6. Print the Print Settings by pressing the GO button three times. If
the Print Settings pages do not print and the Paper LED is on again skip
to the next section - No Paper in the Paper Cassette.

If the Print Settings pages print, the problem is isolated to printing
from your computer. The Paper Source of the Brother printer driver or
program you are printing from may be set to MP Tray or Manual, instead
of Auto Select, Tray 1, or Tray 2 (if the optional paper tray is
installed). To check the Paper Source setting of most programs, click
File and Page Setup or Page Layout. You may need to click the Paper
Source tab or Paper tab depending on your software application. Verify
that in the Paper Source section does not list MP Tray or Manual. Choose
Auto Select, or another relevant source such as Tray 1. Click OK. Try printing the document again.


No paper in the paper cassette.
1. Pull the paper tray completely out of the printer.

2. Insert the letter or legal size paper into the paper tray with the
top edge of the paper first and the print side down. Make sure that the
paper is flat in the tray and below the maximum paper mark. If using a
paper size other than letter or legal, the paper should be loaded in the
MP Tray. The MP Tray can print on paper from 2.75 in. by 4.57 in. up to8.5 in. by 16 in.

3. While pressing the blue paper-guide release lever, slide the paper
guides to fit the paper size. Make sure that the guides are firmly in
the slots. For legal size paper, press the lever located at the back of
the tray and pull out of the back of the open tray.

4. ReinstalI the paper cassette back into the printer. Press the GO
button. If the alarm clears, no further troubleshooting is needed. If
the alarm continues, follow the steps below.


Paper Jam at Paper Pick-up.
1. Turn the printer power switch OFF on the right side of the printer.

2. Remove the paper cassette from the printer.

3. Elevate the front of the printer slightly to locate the jammed
paper.

4. Gently remove the jammed paper.

5. ReinstalI the paper cassette back into the printer.

6. Turn the printer power switch ON. If the alarm clears, no further
troubleshooting is needed.

When a paper jam occurs, the printer will stop printing and the Continue (1) and Paper Jam (2) lights on the operator panel will come on. See the illustration below.
When you experience a paper jam, it is recommended that you check and clear the entire paper path. To clear a paper jam, do the following:

1. If you are feeding paper from a paper tray, first remove the tray. Look for and remove any jammed or damaged paper you find.
   
   
   
2. Open the front cover and remove the print cartridge assembly.
   
   IMPORTANT! Do not leave the print cartridge assembly exposed to direct light, especially sunlight, for an extended period of time. Extended exposure to light will damage the green photoconductor roller and cause print quality problems.
   
   
   
3. Remove any paper you find jammed in the area behind the print cartridge assembly.
   
   
   
4. Also lift the flap at the front of the printer and remove any paper you find jammed beneath the flap.
   
   
   
5. Open the rear exit door/cover of the printer and remove any jammed paper you find there.
   
   
   
6. Once you have confirmed that the entire paper path is clear, reinstall the print cartridge assembly. Close all the printer covers/doors. Reinstall any paper trays you removed.
   
7. Press the Continue button to resume printing. NOTE: The printer should reprint the page(s) that caused the paper jam.
   
8. If the paper continues to jam, press the Continue button twice quickly while the Continue and Paper Jam lights are on. This will cause the operator panel to display the secondary error paper jam light sequence. The secondary error code will tell you where the printer thinks the problem has arisen. For more information, see the 'Secondary Error Codes' section on page 69 of the User's Guide.

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