Hp 530 wont boot

There are plenty of possible causes. We would need a whole lot more information to make any recommendations.

It is a laptop (if I am not mistaken) so your available options are very very few for getting this thing to work.

If the problem is windows, take out your hard drive, connect it to another computer through USB (buy connector first), back up your files, then do a fresh install using your Windows CD.

Right now I think your problem is Windows simply because no information has been provided.

Try providing some more information, for example do you hear any beeps? Have you changed any hardware or software recently in your computer? etc..