I have an OKI 831 DN printer hardly used with a cover open fault on startup, everything else is ok.

SOURCE: HP Deskjet 5150 - top cover open

I had the same problem, and the cause turned out to be the cover switch not being fully pushed in. On the underside right edge of the top cover, there's a little triangular protrusion that pushes down a black rectangular button (the cover switch) when the cover is closed. The problem occurs because the flimsy top cover is made of plastic and flexes slightly when you close it. This means that sometimes, the right edge of the cover won't seat properly even though it appears as if the cover is closed all the way. When this happens, the triangular protrusion isn't fully pressing the switch down.

To test if this is this is happening, send a print job to the printer and wait for the "top cover is open" error message to appear. Next, open the top cover door and locate the cover switch. It's a little black button in a rectangular hole at the right edge of the doorway near the ink cartridges. Take a pen or a car key and use it to push the cover switch down. You can also use your fingertip to do this if it's skinny enough. If you keep the cover switch pressed down, the power button should start blinking to indicate a print job is coming through. If the print job actually starts printing, then you know the problem was the cover switch.

In my case, all I had to do the fix the problem was close the cover and make sure it was fully seated by firmly pressing down the right edge of the cover until I heard a plasticky "click" noise. After that, the problem went away.

Hope this helps.

SOURCE: my mp600 keeps saying close inner cover-which is closed

I had the same issue, turning off didn't solve it.
There's a plastic flap the width of the print tray just inside that I flipped up and it solved this problem. It is directly in front of the ink tanks. I'm assuming we flipped it down and forgot about it. It seems it needs to stay up, although you wouldn't notice it when it flips down when you close the top, as it closes just fine with it down. It's easy to overlook. This took me a few hours to realize.

The top of the flap has a half circle cut out of it in the middle.

SOURCE: I have a Kyocera FS-2000D printer that will not print

first turn off your pritner power.
check open the front door pull your ink cartridge then clean dust and blur from it then check there is not any paper jam then refix ink cartridge.then turn on the power.

SOURCE: How do l reset my OKI c9650 yellow drum, l have

some password need, when "System Maintenance" is displayed... :-(

SOURCE: paper jammed at this time error message show on

This error comes when media doesn't come to fuser delivery sencor with in the specified time it may be due to improper paper picking or fault in registration ***...
clean the paper feed rooler & registration *** path ur problem will resolve defin...........