We have 4 of the above printers and recently 3 have became quite messy with a coating of an overspray like coating on the inside of the printer case, the mechanism, and underneath. This was discovered as one of the printers was to be moved and here was this coating all over which got on fingers and anything it touched. It did clean up by wiping, however, only 3 of the 4 had been effected. The 4th printer (uneffected)is less active, but this only recently surfaced. What could be the problem? I have been using HP DJ's for several years and have never witnessed anything like this? Anyone having had similar experience, cause and solution please respond. I question the cartridges as the 3 have in the recent past changed cartrides while the 4th has not. We use only HP new replacment cartridges.