There is no point in trying to get in contact with HP for two reasons:
1. Your notebook has been out of warranty for years, and you will have to pay HP to even talk to them once you provide the serial number for your notebook.
2. HP quit selling recovery disks for your notebook's model series many years ago, so they are not available.
If you can still read all 25 characters of the W7 product key on your notebook's case, let me know, and I will give you a way you can create W7 installation media to reinstall W7 if the key is good for Home Premium or Professional.
The only thing I don't know is if the key on your notebook will work to activate Windows for notebooks sold in India.
I know it works for PC's sold in the USA and Canada.
Anyway, you can try it and see if you can read all 25 characters of the W7 product key.
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