Deskjet HP 6940

You may need to do an alignment of the print cartridges. 1. Open the HP Solution Center 2. Click on Settings 3. In the Print Settings section, click Printer Toolbox 4.Click Align the Print Cartridges 5. Click Print Page An alignment page will be printed. Placed the alignment sheet with the printed side down on the right front corner of the scanner glass. Press the scan button to complete the alignment.

Print a diagnostic page If the steps above have not helped, print and evaluate a diagnostic page to see if the cartridges or the printer is causing the problem.

1. Make sure the printer is on and loaded with unused, plain, white paper.
2. Press and hold the Power button and then press the Cancel button. Release both buttons. The diagnostic page prints. Figure 1: Power and Cancel buttons 1 - Cancel button 2 - Power button

Step 4: Note which cartridges printed which areas of the diagnostic page You must identify which cartridge printed which part of the diagnostic page, so that if you find defects on the page, you will know which cartridge is the problem. However, you can install different combinations of print cartridges in your printer, and different cartridge combinations print different diagnostic page patterns. Your diagnostic page may not look exactly like the picture below, but the right and left cartridges will print in the same areas of the page no matter which cartridges are installed. Figure 2: Diagnostic page layout (the patterns in each area may look slightly different on your page) 1 - Printed by the right cartridge 2 - Printed by the left cartridge NOTE: If you are printing in reserve mode (one cartridge is missing), the missing cartridge's area of the diagnostic page will be blank. Step 5: Check ink levels NOTE: If you have installed a refilled or remanufactured ink cartridge, or a cartridge that has been used in another product, the ink level indicator is inaccurate or unavailable. Look in the middle of the diagnostic page. The bars with "E" (for "empty") and "F" (for "full") at each end show the ink levels in the cartridges. As ink is used, the solid color changes to a faded color. Figure 3: Left (tri-color) cartridge almost full - right cartridge empty Figure 4: Both left and right cartridges almost full

This problem is mainly due to driver corruption
1. Reinstall the driver or scan for viruses and remove it.
2. Remove all temp files from the drive.
3. Try removing corruption in OS or reload OS.
4. Try connecting to another system and take print out.
5. Chipset on the printer may be having problem, get it serviced.

This could be a problem with the paper your using. Try another brand of paper that is recommended only for the inkjet printer. Paper that is meant for Laser does not always work will with inkjet printers as it is made to handle toner and not ink.

Some paper I suggest is the HP Brochure paper C7020AC 48lbs which is recommended for your printer by Hewlett Packard. If not available try and see if you can get something similar that is only for inkjet printers. 8.5 x 11 in, 48 lb, 100 sheets C7020AC

you'll need to reset the print mode to single-sided, also check the print/text size

could be the page .
go to print preview. see if you can see the text overlay.
usually the printer prints exactly what is in the preview.

Hi,

This generally happens when,
The paper is mismatched to the paper setting for the printer.

For example, if you are using high-quality photo paper, set the printer's output for that paper; do not use the plain paper setting.

Post your response about how things turned up and i can help you up from there.....

test page printing but doc files not printing....

HP DeskJet 6940

I think the problem is now fixed: I reinstalled the HP printer drivers, and made sure to choose HP DeskJet 845c in the printer setup before I printed a document. 

I have the same issue, but with a HP DJ 3550, I´ve heard about the data execution protection (DEP) migth help when changing the options, but still have to try it