There are paper path cleaner sheets that you can get at supply stores or on line. They are sticky on both sides. They pick up paper dust from the rollers as it passes through the printer.
Looking at the operation panel, to left and slightly underneath it is the scanner lock. There are symbols on it with a padlock. Slide the catch to the unlocked position. You probably caught the catch and unwittingly locked it or partly locked it.
The machine is failing to initialise. If you can get it into download mode then its possible to flash the eeprom with the latest version from OKI's site
The low voltage power supply is located in the bottom right side of the machine. Remove the right side cover and you will see it at the bottom of the machine. It is the full length of the unit. All you can do is check the fuse but its unlikely to be at fault unless there was a power surge at some time. If the PSU has blown then the cost of a new one and fitting will be more than half the value of the whole machine.
Okidata B710 and B720 Maintenance Reqd. Reset Procedure
To enter the Diagnostics area:
Turn the printer power OFF.
Press and Hold the MENU^ and Enter buttons.
Turn the printer power ON (you can release these buttons as soon as "loading ... '' is displayed.
The Operator Panel reads "Diagnostics"
There is a list of Test Options and settings.
Press the Down Arrow highlight "Maintenance Info." Press the Enter button
The Operator Panel Display reads "Maintenance Info" with setting listed.
Reset Maintenance reqd. is highlighted. Press EnterReset Maint. Reqd. is displayed and Execute is highlighted.
Press Enter.
The Display reads - Resetting Maintenance Required.
This completes the process.
The usual cause of "fake" paper jams is a prior "real" paper jam. One of two things occurs.
A small bit of paper tears off the jammed stock and hides from view, but keeps the printer jammed. These can be hard to find and remove, depending upon where they are.
In the process of yanking the jammed paper out of the unit, the sensor(s) become damaged or misaligned and give false jam indications. This usually needs repair or replacement.
when cover open in oki c 301 dn then push pull switch is UN link and information show cover open in printers or copiers. just change push pull switch or clean that with ctc the switch you can search on casing were the cover is close and can push that.
