Jam at Door E

SOURCE: document jam

There is a sensor in the document feeder that most likely is stuck on the frame or the spring fell off and is not resetting. Have you taken a minela folder and run it through the feeder to be sure there is not a small fragmant of paper on the sensors? If you havent try that, or a piece of paper folded in half twice and keep sliding it though the feeder.
You would have to take the feeder apart to get the sensor set, That is best accomplished by taking the back cover off, then the left side cover, ( looking from the front) and disconnecting the feedder connectors, then removing it from the scanner.

SOURCE: After clearing a paper jam,

One of the paper flags is either stuck down or broken (from the area of the jam)

SOURCE: carriage jam error

lift the printhead latch, ther could be some paper stuck in the side , I just did it, now everything is ok!!!!

SOURCE: back cover open message on brother mfc 7820n

Had same problem. Closer inspection revealed bit of paper out of sight. Removed the toner cartridge and worked to free torn paper. Then restart. Hope it helps.

SOURCE: paper jam

when that happens it's one of two things, or your printer needs your Manteinance Kit to be Replaced or it's an Issue related to a sensor that's under the toner cartdrige when that sensor it's dirty, it got stuck and make the machine thinks it has a jam when obviously there's nothing there hope that i could help