HP LaserJet 9050DN
Have a 9050DTN with tray 4 HC input unit that will run a paper path test correctly from the individual trays but when run from all 4 trays the paper from tray 4 feeds out overlapping the tray 3 paper. This happens regardless of what type of paper is in the trays.

How to Identify and Fix Common printer Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced technical support :

The paper might not be engaged with the feed rollers. The paper-width guide is pressed against the paper stack too tightly. The paper tray is not completely inserted into the product. The paper settings in the print driver do not match the paper loaded in the paper tray.
Remove the stack of paper from the tray. Check for obstructions inside the tray. Use a flashlight to view the mechanism inside the tray to make sure that nothing blocks the paper from engaging with the rollers. Even small pieces of paper can cause paper feed issues.
If your printer keeps jamming, you should know that the most common cause of a jam is misalignment of the paper. Paper needs to load in smoothly, completely flush with the tray. Overfilling the tray is a great way to ensure you will be spending some personal time getting to know the inside of a printer.
Dust, paper fiber, and other debris might accumulate on the pick rollers and cause paper feed issues. To help prevent paper feed issues, clean the rollers inside the printer and in the duplexer (if equipped). If the other steps in this document fail to resolve the issue, then reset the printer.
If the paper feed rollers are dirty or paper powder is attached to it, paper may not be fed properly. In this case, clean the paper feed rollers. Cleaning will wear out the paper feed rollers, so perform this only when necessary. Make sure that the power is turned on and remove any paper from the rear tray.
Your printer can become misaligned if there is any paper stuck in the machine, print cartridges are clogged or dirty, improper installation of cartridges and using low quality cartridges. Additionally, a printer can become misaligned after the machine completes a large print job.
The common reasons for this issue are various, for instance, the paper input tray is overloaded, dust or moisture can affect the paper feed or paper pick rollers, the printer driver is old, etc. Thus, the printer cannot detect the paper that has been inserted into the tray.
Paper Overloading

Because many desktop inkjet printers are top-loading, it can be easy to overload the tray.

The paper has holes along both sides that fit over the sprockets located on the feeder wheel. When the wheel turns, it feeds the paper into the printer. The holes are torn off the paper after the printout is complete. And, yes, printers still use this type of feeder mechanism.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My printer feeds through one piece of paper all the way and then a half piece of paper and stops. I pull out the paper to stop the paper jam and then it prints but sounds rough. After printing, it doesn't feed the paper all the way through.
ANSWER : And the first 2 sheets, the full and half sheet that go through first, are blank.

Read Full Q/A … :

HP LaserJet 9050DN

Paper jam in tray 2 (but no paper pulled from tray) also M476DN models
ANSWER : Isopropyl alcohol is not recommended for rubber rollers. It dries out the rubber and hasten it’s cracking and breaking. It will do nothing to restore the grip. Those rollers are really hard to replace. It would be easy if that dumbass secondary menu really worked. None of the techs I’ve spoke to ever got into it. Everyone I know sends a print job and listens for the roller to rotate into position where you can pull it off.

Read Full Q/A … :

HP LaserJet 9050DN

Tray 1 (upper tray) paper feed problem
ANSWER : There is no way of adjusting the distance of lift. Could be that the pickup roller is worn enough that it will pick up a sheet that is higher, but not one that is lower down. You can look at the end of the roller that first makes contact and see if it is worn smooth.

Read Full Q/A … :

HP LaserJet 9050DN

Tray 2 solenoid part found under printer; Paper feed issue
ANSWER : What you are describing sound like the solenoid plate and return spring. If you look at the plate itself, you’ll see a lip curling up on one end and there are 2 slots on the sides at the other end. The lip is what stops the roller from turning until the solenoid pulls the plate down. The slots go on the 2 poles sticking up on the solenoid with the lip pointed up. Then you hook the spring on the 2 metal tabs one on the solenoid body and the other between the 2 slots at the back of the plate.

Read Full Q/A … :

HP LaserJet 9050DN

Canon Pixma Printer Paper Does Not Feed Properly/"No Paper" Error Occurs?
ANSWER : Pretty much useless advice. I also have serious doubts about someone who is obviously not fluent in the English language.

Read Full Q/A … :

HP LaserJet 9050DN

LJ 4250N Tray 2 Clearing Paper Path 41.3 Error
ANSWER : i saw sAme problem in my client printer hp lj 4250 . its toner problem . when i am the toner change then printer is 100% ok.

Read Full Q/A … :

HP LaserJet 9050DN

hp 8600 pro when power on, paper jam message appear but there is no paper jam in the tray
ANSWER : Hp 8180 Photosmart All In One code keeps says paper jam and carriage jam when neither are jammed. I followed all the recommended things to do. I live in Raleigh NC any place to take this or any suggestion.

Read Full Q/A … :

HP LaserJet 9050DN

Paper Feed Problem on HP R80
ANSWER : In the last examination it is our origination of death which chooses our responses to all the inquiries life puts to us. The most pleasant spot to be is in somebody’s idea; the most secure spot to be is in somebody’s petitions.

Read Full Q/A … :

HP LaserJet 9050DN