A toner cart does alot for what it is. Besides a toner supply it has a shutter, wiper, mylar film(can be marred), and mech. assy. to mesh to the gears. During S/H it may have dropped some toner and/or got loose, etc.. Especially true if the toner cart was shipped already installed. Usually, a new toner cart fixes many a typical problem, however not all. You should use the wiper(green?, review manual) that you use to wipe down the area via some track. Vacuum out the immediate area. Be sure the gearing has no foreign objects and the toner cart fully seats. That no mess or damage is found in the "fuser area" as well as use of so-called "cleaner paper" for fine cleaning. In no way may this fix you problems, besides a cart replacement, but you can say, you did this and that. Remember, shipping a heavy object like a prtr. can be handled rough or at least not as well as like. However, if still unhappy, return the prtr. Yeah, you may not find another low-usage unit, but you can't have your cake and eat too, otherwise you'll be stuck with it.
tada -----Willy 
I've just bought a used HP LaserJet 2300dn printer on ebay. The seller's had lots of good feedback, sold lots of printers, which was a factor in buying it from him. When I got the machine, it was as described. Cosmetically it is perfection. However when I print the quality is awful, with gray roller marks, that are consistently fused into the paper. So I went into the menu and produced a cleaning page and ran this through the printer several times with no effect.
I've been in touch with the seller, who says that it left fine and I can send it back, but it would be difficult to find a printer that has similarly low page count (only 10k, which is great for this age printer).
So I ducked in to a local computer service shop to see if they had any suggestions. I was told that this was probably because I needed to replace the toner cartridge (which the salesperson sold)...but that seemed odd: if it was low toner, I'd have thought the print would simply start to fade, not produce these consistent, dark gray roller lines on the park. He also suggested removing the toner cartridge and passing a vacuum cleaner inside the assembly, which I've done, without any noticeable improvement.
Does anyone out there have experience with this kind of thing? Any other suggestions or is this indicative of a duff printer?
THanks in advance for advice and suggestions.
Gus
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