my activation key for windows 8 release preview build 8400 didnt work.or it is wrong for my windows so i need other activation key.
If you are referring to Windows 8.1 Release Preview, you could enter the product key mentions in FAQ:
All of the Windows 8 Preview versions was expire on January 15, 2013. If you are referring to Windows 8.1, please follows Cyber’s response.
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