I am using Acer Aspire 6930g. . . recently formatted my system and trying to install windows vista home premium from one my friend and am using my poduct which i got with my laptop . . . but it says Product key is not valid . . .

please help me . . . . 

Diagnostic Report (1.9.0011.0):

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WGA Data-->

Validation Status: Invalid License

Validation Code: 50




Windows Vista Home Basic Oemact Acer Incorporated Download