Beginner need help on weird focusing of Nikkor 18-200mm

[mungkey]

Hello guys,

I was wondering if it was ok to ask for help or just ideas here about this nikon 18-200mm lens that i have on a nikon d80. It is able to autofocus in wide and mid distances but when i zoom in to 200mm it cannot achieve focus. Everything is blurry even if i switch to manual and turn the focus ring myself. Im kinda new to these things and i dont know if it is something i need to get fixed or its a normal thing. i got the camera in some auction site a few months ago but was not able to use it heavily because i got busy with my dayjob. Now when i took it out of the storage bag, I noticed i cannot focus when i zoom and then focus to far places. I did not experience this before when i first used it. It's autofocusing quite well when i go to the lower end tho ... in the 18mm up to 70mm. I'm sad about what happend and just dont know what to do with it now... Is there any fix to this. Any thoughts would be greatly appreciated.