I have an HP OfficeJet G85xi, and it keeps displaying a "paper jam" error. There's not paper jammed, and the back rollers keep spinning every time I turn the machine on. I've wiped those rollers clean, but same problem occurs. The machine is from about 2002, and works perfectly, except for this issue. I hope there's a fix for it.

SOURCE: carriage jam/officejet G85xi

SolutionStep one: Perform a power reset and connect the printer directly into the electrical outlet Remove all the paper loaded in the main input tray.
Make sure that the product is turned off. 
Disconnect the USB cable from the back of the product.
Disconnect the power cord from the product.
Disconnect the power cord from the electrical outlet and wait 10 seconds.
Reconnect the power cord directly into the electrical outlet and check for the following.
Make sure that the power cord used is the one provided with the product.
If a computer is connected to the product, make sure that the computer is connected to a grounded (three-prong) wall outlet.
Make sure that the power cord is firmly connected to both the product and the power supply.
Reconnect the power cord to the back of the product.
Press the power button ( ) to turn on the product.
Reconnect the USB cable to the back of the product.
If the issue is resolved, proceed to Step six: Print a self-test page.
If the issue continues, proceed to the next step.

for more information please go to below link>>

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01458822&cc=us&lc=en&dlc=en

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SOURCE: I have an HP OfficeJet

Hello there, paper jams are usually caused by 2 issues. The first being paper components being holed up inside the unit either whole sheets or torn fragments of paper. In this case all you have to do locate the paper fragments and remove them gently from inside the unit.
The second likely cause is the failure of one or more of the sensors in the unit. When the sensors in the unit fail it is usually as a result of a multitude of factors but basically getting the sensors to function back means 1 of 2 things. The first being to get the system memory cleared up and secondly is to replace the sensors and clear the system memory. Either of these are user servicable and require expert help and considering that HP does not support this unit again due to the age the cost to get these done would probably cost a replacement printer and repairs of this nature carry no guarantee. You can attempt to contact HP on this for a price quote or just replace the printer, but i would go with just replacing it. Sorry for any inconveniences.
Hope this support has been helpful?
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