I had the same problem with a Mintek 1600 DVD player. Put disk in, main "mintek screen comes up on tv, and get no disk found error. I followed these directions and it worked. For the 1600, UNPLUG unit, remove outside cover screws, remove lid. Find DVD unit, remove 4 screws for cover plate, there is the laser lens unit, Gently rotate the gears or the unit with your finger to get the unit in and out a few times ( i did about 4-5 times). Replace cover and 4 screws, replace outer cover and 6 screws. Plug in, chose CD of your choice, U2 worked really well for me, and hit the PLAY button. Mine made some odd noises and played, at first you could tell the music was a bit off, but by the end of the album it was fine. (Unit is recalibrating)Hooked it up to the tv, dvd in, hit play and Bingo works again. Kudos to "Helper" for this great hint.
Tom Walsh, December 2006