Even though cassette is loaded it keeps saying "add paper in cassette" and will not print

It is possible that your Epson WF-7820 is experiencing a paper jam or a misalignment of the paper cassette. If the paper cassette is not correctly inserted into the printer, the printer will display an error message that tells you to insert the cassette correctly. To resolve this issue, make sure the paper cassette is correctly inserted and that any paper jams are cleared. If the issue persists, try resetting the printer by unplugging it and then plugging it back in. If the error message still appears, contact Epson support for further assistance.
Loading Paper in Cassette 1 (Upper Cassette)
https://files.support.epson.com/docid/cpd3/cpd39348/Source/Printers/Source/Paper_Loading/Tasks/XP800/loading_paper_upper_xp800.htmlfaq-207896 ' SPT_C11CB58201 ' Epson WorkForce WF-7520 ...
https://epson.com/faq/SPT_C11CB58201~faq-207896?faq_cat=faq-topFaqsWF-3820 Series User's Guide
https://files.support.epson.com/docid/cpd5/cpd58812.pdf

mp tray folds down right below the toner cartridge cover its looking for a size paper you don't have loaded in cassette therefore its asking you to load that size in mp tray

Try this fix:

Where the cassette goes in there is a sensor that paper hit when it inside of it is broken or Knox out of position with cassette out try pressing on switch you might also have to tell it that cassette is in place could a another sensor might have to take a piece of paper slide between sensor

I was also stuck with this error message for a while. It turned out to be a 4x6 photo paper got stuck in back in a place that was not easily visible. I had to detach the double-sided paper module from the back, tilt the printer on its side and reach in with fingers and pliers to pull it out. The error message was correct, that something was blocking the cassette tray even though you could push the tray all the way in!

The light means that the printer is out of media, or the media did not feed properly

What you can do

-Load media into tray and press Continue button to resume printing.

-Check that the media is loaded correctly in tray

-Press Cancel button to cancel the print job.

I had this same problem and tried everything (I thought) to fix it. Then I saw the solution at:
http://www.retrevo.com/c/sohohelp/blogs/show/6633/I-just-had-my-espon-artisan-800-replaced-and-the-refurb-keeps-saying-that-the-paper-cassette-is-not-seated-correctly#replyForm

Basically there is a plastic pin that tends to break off and stays in the area where the cassette is loaded. It takes up just enough space to keep the cassette from being pushed in all the way. The solution is to turn the printer off, unplug it, then lift up the printer so the broken pin falls out. Once it comes out, the printer will work fine again.

PIXMA MP620 has 2-way paper feeding. Check your proper paper feeding. Rear feed or bottom cassette paper feed.

If you have paper in the loading tray and it keeps giving you out of paper message then the sensor by the loading hopper is not working and would need to be replaced.

9 times out of ten though you might want to clean the printer and make sure the hopper is not just jammed this happens when you put too much paper in there at one given time.


thanks

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/edwy_1a56970cf1ea4620

Hi ...

Most of the time this problem comes when the paper is not loaded correctly. Follow the below instructions to load papers to the cassette and I am sure this will resolve your problem. I will keep monitoring your responce and if required, i'll look for a work arround.

Follow this procedure to load paper / envelope in the cassette:

1. Pull out the cassette from the machine.
   
   
   
   
2. Remove the cover from the cassette.
   
   
3. Fan out the sheets of paper so that they do not stick together.
   
   
4. Align the edges of the paper.
   
   
   
   
5. If the cassette is not yet extended, use your thumb to press the tab (indicated by the pink circular outline) and release the latch.
   
   
6. After the latch is released, remove your thumb from the tab. Then extend the cassette until a click is heard.
   
   
   
   
7. Load paper on the upper-right corner of the cassette with the print side facing down.
   
   Note:
   * Since the Credit Card sized paper, Canon Photo Stickers, and Legal sized paper cannot be fed from the cassette, load them in the auto sheet feeder (ASF).
   * When loading A5 or larger sized paper (nonstandard-size paper: 203mm / 8inches or more in length), extend the cassette by pinching the tab.
   
   
   
8. Grasp the paper guide (A) and align it to the long edge of the envelope stack (2). Align the front edge of the paper stack in the same way (3).
   
   
   
   
9. Close the lid and push the cassette all the way into the printer.
   
   
10. Press the <Open> button and pull out the extension completely.
    
    
11. Press the <Feed Switch> button to turn on the Cassette light.
    
    
    
    *MP500 shown.
    
    Note:
    If the Auto Sheet Feeder lamp lights, press the Feed Switch button to light the Cassette lamp.
    If the Cassette lamp does not light even after pressing the Feed Switch button, Paper Source in the printer driver may be set to the setting other than the Feed Switch button.
    

Loading on envelopes
Paper Type
Precaution
Envelope (DL / #10 )
Set paper with the flap closed.

1. Press down firmly on the edges of the envelopes to make the folds crisp. Also, press firmly on the area that corresponds to the edges of the back flap.
   
   
2. Remove any curling by holding the edges diagonally and bending them gently.
   
   
   
   
3. If the edges of the envelope are inflated or are curling, place the envelope on a flat surface. With a pen, press down while moving it from the center toward the edges of the envelope.
   
   
4. Ensure that no curl or puff exceeds 1/8 in. (3 mm).
   
   
5. Load envelopes in the cassette with the print side facing down and the flap towards the left.
   
   
   
   
6. Close the lid and push the cassette all the way into the printer.
   
   
7. Press the <Open> button and pull out the extension completely.
   
   
8. Press the <Feed Switch> button to turn on the Cassette light.
   
   
   
   Note:
   If the Auto Sheet Feeder lamp lights, press the Feed Switch button to light the Cassette lamp.
   If the Cassette lamp does not light even after pressing the Feed Switch button, Paper Source in the printer driver may be set to the setting other than the Feed Switch button.
   

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