I bought this Nikon Lens (Nikkor 18-200mm f/3.5 - 5.6 VR) 2 years ago and love it. A month ago it didn't focus at 200mm at infinity anymore - completely blurred pictures. The guys at the http://www.dslr-forum.de helped and told me that probably the front lens got loose. I screwed off my filter and saw that there are two small points where you can unscrew the lens. The lens was very loose. Just for fun I unscrewed it totally, cleaned it and put it on again. Now it's working fine again!