Photoshop CS? As in ancient Photoshop 8.x? ?? !!
First, you would need to make sure that the Camera Raw plug-in you have installed is at least ACR 2.4.
Then look for, download, install and run the free, stand-alone Adobe DNG converter 8.6 on your raw NEF files in order to convert them to raw DNGs that you can then open in ACR 2.4 or higher.
You should take note that you will be leaving a lot of quality on the table by using such an old version of Camera Raw. ACR (Adobe Camera Raw) has come a long, long way since then.
For next time:
If you give complete and detailed information about your setup and the issue at hand, such as your platform (Mac or Win), exact versions of your OS, of Photoshop and of Bridge, machine specs, such as total installed RAM, scratch file HDs, video card specs, what troubleshooting steps you have taken so far, what error message(s) you receive, if having issues opening raw files also the exact camera make and model that generated them, etc., someone may be able to help you.
Please read this FAQ for advice on how to ask your questions correctly for quicker and better answers: