Q: I need a cleaning kit for the HP 4250n laserjet, there is a small black toner smudge on the upper right corner of every page
A: Hello, If you are only getting 1 mark on the page then most likely there is toner laying on the paper path. If it is a repetitive mark meaning showing up in multiple lengths down the page then most likely it is a defective part in the printer. Assuming it is the first item (only dirty) then, after removing the toner cartridge, you should either use a clean cloth and wipe out the printer and any toner laying about. Another way is to take a can of air, or compressed air, or even a vacuum cleaner in reverse (so it blows air) and blow the toner out of the printer, then wipe it down inside. As a general rule laserjets should never be cleaned on the inside with anything that is wet, only the outside gets cleaned that way! After cleaning the first few pages will most likely come out dirty, or grayish in color but will get a lot better afterwards. Good luck!