Hello. I understand you are having issues with the printing quality when you print out documents?
Well, the first thing that you would need to do is make sure that the drum and the toner cartridges are seated properly. Remove the drum and cartridgesand put them back in, being careful not to touch the electrodes or to spill any toner. Secondly, if the drum has gotten toner in it, clean the drum unit as best as you can without using ANY chemicals.If those steps don't work, go to http://support.brother.com/g/b/midlink_os.aspx?c=us&lang=en&prod=hl4150cdn_all&site=pc&type2=4&orgc=us&orglang=en&orgprod=hl4150cdn_all&targetpage=18 to update your firmware.If none of these steps work, then the cartridge or the drum may have gotten damaged somehow. Let me know if any of this helps.
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