The read out display states Cartridge error 1203, refer to user manual

ERROR 1203 LEXMARK ERROR 1200 Error 1203 is an issue that occurs either when a cartridge is bad or the printer cartridge Slot is bad...

1 - try cleaning the copper contacts of the both carts and cart slot in the printer and try again..
or
2 - when error shows up, shut the printers power off; wait one minute and turn it back on press copy.
Or try

Reset Factory Defaults on the Dellâ„¢ 964 or 966 Printer

To reset factory defaults on the printer, perform the following steps:

1. Press the down arrow button until Maintenance is highlighted and press the Select button.

2. Press the down arrow button until Reset Defaults is hightlighted and press the Select button.

3. The printer displays a confirmation message. Highlight Yes and press the Select button

Note:
Some settings such as phone lists, time, date, and country are not changed.

Please come back and just gave a vote, it will gave me some satisfaction to know am helping some one so I will keep on helping.

All The Best: Pineworks

Error 1203 is an issue that occurs either when a cartridge is bad or the printer cartridge Slot is bad...

1 - try cleaning the copper contacts of the both carts and cart slot in the printer and try again..
or
2 - when error shows up, shut the printers power off; wait one minute and turn it back on press copy.


All the best Pineworks

The error 1203 error message on the operator panel could indicate a problem with one of the ink cartridges. Please follow the steps given below:

1. Please make sure the All-In-One is powered on.
2. Pull the control panel towards you, and then open the cartridge access door. The print cartridge carrier moves and stops at the loading position.
3. Pull the old cartridges towards you, and then lift them out.
4. With the cartridges out of the printer, shut the access door and the control panel.
5. Power the printer OFF and then back ON.
6. Please check the operator panel to see if the same error has returned or if a new message has appeared.
7. If the message displayed is 1203, there is something wrong with the printer hardware.
If the message now displaying is Cartridge Missing, do the following:

1. Reinstall the cartridges into the printer.
2. Insert the color cartridge in the left carrier. Insert the black cartridge in the right carrier.
3. Push back firmly on the cartridges until they snap securely into place.
4. Close the cartridge access door, and then close the control panel.
5. If the 1203 message is still present on the operator panel, you need to insert one cartridge at a time to determine which cartridge is producing the failure.
6. With one cartridge in the carrier, close the access door and control panel.
7. Please check the operator panel. If the 1203 error is displayed, this cartridge is the defective item. If the Cartridge Missing message is displayed, the second cartridge is producing the failure.
8. Please replace the defective cartridge.

cant find a user manual, only install manuals :(

from reading on your error it seems to point to an ink cartridge issue have a read of some of the following links

http://www.fixyourownprinter.com/forums/printer/38960

http://www.fixya.com/support/t131154-error_1203

loads more, just search lexmark x4270 error 1203

The error 1203 error message on the operator panel could indicate a problem with one of the ink cartridges. Please follow the steps given below:
1. Please make sure the All-In-One is powered on.
2. Pull the control panel towards you, and then open the cartridge access door. The print cartridge carrier moves and stops at the loading position.
3. Pull the old cartridges towards you, and then lift them out.
4. With the cartridges out of the printer, shut the access door and the control panel.
5. Power the printer OFF and then back ON.
6. Please check the operator panel to see if the same error has returned or if a new message has appeared.
7. If the message displayed is 1203, there is something wrong with the printer hardware.
If the message now displaying is Cartridge Missing, do the following:

1. Reinstall the cartridges into the printer.
2. Insert the color cartridge in the left carrier. Insert the black cartridge in the right carrier.
3. Push back firmly on the cartridges until they snap securely into place.
4. Close the cartridge access door, and then close the control panel.
5. If the 1203 message is still present on the operator panel, you need to insert one cartridge at a time to determine which cartridge is producing the failure.
6. With one cartridge in the carrier, close the access door and control panel.
7. Please check the operator panel. If the 1203 error is displayed, this cartridge is the defective item. If the Cartridge Missing message is displayed, the second cartridge is producing the failure.
8. Please replace the defective cartridge.

The error 1203 error message on the operator panel could indicate a problem with one of the ink cartridges. Please follow the steps given below:

1. Please make sure the All-In-One is powered on.
2. Pull the control panel towards you, and then open the cartridge access door. The print cartridge carrier moves and stops at the loading position.
3. Pull the old cartridges towards you, and then lift them out.
4. With the cartridges out of the printer, shut the access door and the control panel.
5. Power the printer OFF and then back ON.
6. Please check the operator panel to see if the same error has returned or if a new message has appeared.
7. If the message displayed is 1203, there is something wrong with the printer hardware.
If the message now displaying is Cartridge Missing, do the following:

1. Reinstall the cartridges into the printer.
2. Insert the color cartridge in the left carrier. Insert the black cartridge in the right carrier.
3. Push back firmly on the cartridges until they snap securely into place.
4. Close the cartridge access door, and then close the control panel.
5. If the 1203 message is still present on the operator panel, you need to insert one cartridge at a time to determine which cartridge is producing the failure.
6. With one cartridge in the carrier, close the access door and control panel.
7. Please check the operator panel. If the 1203 error is displayed, this cartridge is the defective item. If the Cartridge Missing message is displayed, the second cartridge is producing the failure.
8. Please replace the defective cartridge.

Error 1203 is an issue that occurs either when a cartridge is bad or the printer cartridge Slot is bad... I would request you to try cleaning the copper contacts of the both carts and cart slot in the printer and try again..

1: Make surethe All-In-One is powered on.

2: Pull thecontrol panel towards you, and then open the cartridge access door.The print cartridge carrier moves and stops at the loadingposition.


3: Pull the old cartridges towards you,and then lift them out.
With the cartridges outof the printer, shut the access door and the control panel.
Power the printer OFFand then back ON.
Check the operator panelto see if the same error has returned or if a new message hasappeared.
If the message displayed is 1203,there is something wrong with the printer hardware.
If themessage now displaying is Cartridge Missing, do thefollowing:

4: Reinstall the cartridges into the printer.
Insert the color cartridge in the left carrier.Insert the black cartridge in the right carrier.


5: Push back firmly on the cartridges until they snapsecurely into place.
Close the cartridgeaccess door, and then close the control panel.
If the 1203message is still present on the operator panel, you need toinsert one cartridge at a time to determine which cartridge isproducing the failure.
With one cartridge in thecarrier, close the access door and control panel.
Check the operator panel.If the 1203 error is displayed, this cartridge isthe defective item.
If the Cartridge Missing messageis displayed, the second cartridge is producing the failure.
Please replace the defective cartridge.

This link should have the answer for you.
http://www.dellcommunity.com/supportforums/board/message?board.id=A940&message.id=13761

To determine whether this error is due to a cartridge failure or a hardware problem with the printer, do the following: Make sure the printer is powered on. Open the printer's top cover. The print cartridge carrier moves and stops at the loading position. Press down on the cartridge lever to raise the cartridge lid. Remove the cartridges. With the cartridges out of the printer, close the top cover. Power the printer OFF and then back ON. Check the operator panel to see if the 1203 error has returned or if a new message is displayed. If the message displayed is 1203, there is something wrong with the printer hardware. Please contact Lexmark Technical Support. If the message is Cartridge Missing, reinstall the cartridges into the printer. Insert the black cartridge in the left carrier. Insert the color cartridge in the right carrier. Snap the lids closed. Close the top cover. Check the operator panel. If the 1203 message is still present, you need to insert one cartridge at a time to determine which cartridge is producing the failure. With one cartridge in the carrier, close the top cover and check the operator panel. If the 1203 message is displayed, that cartridge is producing the error. If Cartridge Missing is displayed, the second cartridge is the defective item. Please replace the defective cartridge.