You need Lightroom 4.1 or later (the current version is 5.7.1 but will not run on Windows Vista or XP and certain Mac operating systems, if that's an issue)
You could also download the FREE Adobe DNG Converter version 7.1 or later and convert your RAWs to DNG and import those into your Lightroom 2.
gary will wrote:
Unable to access nef files from my Nikon D800.
Nor can you expect to - Lr 2 was dead in terms of new camera support, years before the D800 was introduced.
You need to get a newer version of LR. There have been 3 newer versions of LR since you bought LR 2.
You could try using the free Adobe DNG converter program to turn your Nikon NEF files into DNG (Digital Negative) files and then "Maybe" LR 2 could read them.
But in the end you would be better served getting LR 5.