Doesn't Print - Says "Paper Jam"

SOURCE: paper jam ,no paper jam found Dell 1815dn

give this a try

1. Turn off the printer.
2. Remove any paper trays. Inspect them for wrinkled or damaged paper.
3. Also open the back cover of the printer if this model has one.
4. Open any other doors that give access to the printer's paper path and to the toner or ink cartridge.
5. If necessary, remove the toner or ink cartridge. Place it away from light/ sun light to avoid damaging it.
6. If you find a piece of jammed paper, remove it by holding it with both hands and pulling firmly. The goal is to keep the paper from tearing. If several pieces are jammed together, try pulling out the middle piece first to loosen the jam.
7. If the paper does tear, try rotating the roller gears manually to free the paper. Don't force anything, though. Do this step especially if the jam message comes up repeatedly without any obvious paper jam, there may be a small tear of paper inside.
8. Ones the printer is free of paper Replace the toner or ink cartridge and paper trays, close any doors you opened and turn the printer back on.
9. If the printer paper jam message still appears, then there is still some paper in the printer. Reinspect the paper path.
10. see alternative if the problem is still not solved.
    

SOURCE: oki c5250n paper jam

Unfortunately this may require and engineers visit. If you pull down the MP assembly by using the handle in the middle at the front of the printer you can then see a small "gearbox" at the right hand side of the transfer belt. This is common to feeds from both trays and could be worn. If you remove tray 1 and temporarily tape up the sensor arms to fool the printer into thinking it has a full tray installed, you can the test, by applying a little pressure to the feed roller, to see if it positively moves forward or if you are able to stop it turning. On a brighter note, you may just need new rollers instead of cleaning them.