Contact the manufacturer. Usually, for a small fee, you can request a copy of the installation discs. Otherwise, look around at bundled programs, because one of them will probably let you burn your own copies of the installation media.
Some systems even have a special hidden partition that contains copies of these discs, and are set up so that you can boot from them and perform a complete system restore.
I just buy a laptop, but the manufacturer does not give me the OS cd of the Windows Viata. But i got the serial number for it. Someone help me to solve it!!

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