Can't see main screen image in develop module.

Hi There,

I bought a new laptop, have all my files and catalogs already transferred over, and everything seemed to be working until I tried to use the develop module.  I can see the small image on the left top corner, and when I adjust exposure and sliders it changes, the strip of photos from the collection are along the bottom, but where the big main image is supposed to be, its blank grey.  When I switch to the Library module and click on an image, then go over to the develop module, that image is in that big area, but it wont adjust, and it doesn't change to another photo when I click on a different photo from the strip.  There aren't any ! marks indicating the file locations are missing, it just wont bring the image up onto the main screen.  What is going on?  Any help here?