printer says 'out of paper' but the tray is completely full, hp envy inspire 7955e.

Diagnosis

The "Out of Paper" error on the HP ENVY Inspire 7955e, despite a full tray, is typically caused by a failure in the paper pick-up mechanism or a "blind" optical sensor. This model utilizes a sensitive photo-interrupter sensor located at the rear of the input tray. When dust, paper lint, or a tiny fragment of a torn page obstructs this sensor, the printer cannot "see" the paper being pulled from the tray, triggering a false empty alert. Furthermore, this issue often stems from the friction-based pick rollers (the rubber wheels that grab the paper). Over time, these rollers accumulate a layer of paper dust and ink residue, causing them to slip. If the rollers spin without successfully gripping the paper, the printer interprets the lack of movement as an empty tray. You can confirm this by listening closely during the "Out of Paper" error; if you hear the motor spinning but no paper is moving, the rollers are glazed or the sensor is obstructed.

How to Fix It

Follow these precise steps to clear the sensor and restore grip to the pick rollers:

1. Power down the printer and unplug the power cord from the wall to prevent any electrical shorts during cleaning.
2. Remove the paper tray completely from the printer chassis.
3. Turn the printer on its side or tilt it backward so you can see the underside of the paper feed area. Locate the grey rubber pick rollers.
4. Dampen a lint-free microfiber cloth with distilled water (do not use rubbing alcohol as it can dry out the rubber). Gently wipe the circumference of each rubber roller, rotating them manually to clean the entire surface.
5. Locate the small rectangular sensor window at the rear of the paper path. Use a can of compressed air to blow out any accumulated dust or paper fibers. Use short, sharp bursts rather than one long spray to avoid pushing debris deeper into the chassis.
6. Reinsert the paper tray. Load a fresh stack of 20lb white multipurpose paper. Ensure the stack is perfectly aligned and does not exceed the maximum fill line indicated on the tray side-wall.
7. Slide the paper width guides until they are snug against the paper. If the guides are too loose, the paper will skew; if too tight, the paper will arch and fail to trigger the sensor.
8. Plug the printer back in and perform a "Power Reset" by holding the power button for 10 seconds while the unit is plugged in.

If That Didn't Work

• Check for Hidden Jams: Open the ink cartridge access door and look for small scraps of paper lodged in the carriage path. Even a piece of paper the size of a fingernail can trigger a sensor error that mimics an "out of paper" state. Use a flashlight to inspect the far right and left ends of the printer.
• Change Paper Weight: If you are using heavy cardstock or glossy photo paper, the rollers may struggle to grip. Try switching to standard 20lb office paper to determine if the issue is mechanical or related to the specific media type.
• Update Firmware: Navigate to the printer's embedded web server (EWS) by typing the printer's IP address into a browser. Go to the "Tools" tab and check for firmware updates. HP occasionally releases patches that adjust the sensitivity of the paper sensors to reduce false positives.
• Reset the Paper Tray Settings: On the printer's touch screen, go to Settings > Paper Settings. Ensure the paper size is set to "Letter" or "A4" and matches exactly what is in the tray. A mismatch between the software setting and the physical paper length can trigger a sensor error.

Heads Up

• Avoid using "cheap" recycled paper with high lint content, as this accelerates the buildup of dust on the sensors and degrades the rubber rollers faster.
• Never use liquid cleaners or chemical solvents directly on the internal rollers; distilled water is the only safe option to avoid melting the rubber.
• Always fan the paper stack before loading to remove static electricity, which can cause pages to stick together and mimic a paper jam or empty tray.
• If you notice the paper guides are loose or wobbling, do not force them; check for small pieces of debris trapped in the plastic tracks of the tray.