Question for Windows 7 and Nikon users

[Vinny]

I just got a new computer and it is running Windows 7 64 bit. Other than my Serif photo software I use the Windows photo viewer to view the photos, my only other photo viewer is the HP photo viewer on the computer.

I have noticed that when viewing photos using windows explorer that it can read some NEF photos and not others. Was wondering if anyone else had this problem and if there is a solution.

Thanks!