Here are the specs for your HP Pavilion dv6-1446ee Entertainment Notebook Computer. According to the specs, this shipped with Windows 7 Home Basic 64-bit installed at the factory.
If you failed to create your personal set of HP Recovery Discs when you first setup your computer, your best option is to purchase a set from HP, if you can. Please contact HP Customer Support in your region for assistance.
If you unable to purchase Recovery Discs, you can use the information in this HP forum thread entitled "How to Install Windows 7 Without the Disc" to download, create the media, and install Windows 7 Home Basic using the Windows product key on bottom of your computer. Please note that this will not restore any of the HP "value-added" that originally come installed on your computer.
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