First, understand that all raw images with NEF extension are not the same. The specific camera model matters.
Then visit this page to find out what minimum version of Camera Raw is needed to support your specific camera model:
Then visit this page to find out what version of Photoshop that version of Camera Raw works with.
You will either need to update Camera Raw to the latest version that your copy of Photoshop supports (for example, through Help - Updates in Photoshop) -OR- you'll either want to upgrade Photoshop or investigate the use of the free DNG converter.