function getHWID(): String;
var
SerialNum,A,B: DWord;
C: array [0..255] of Char;
Buffer: array [0..255] of Char;
begin
if GetVolumeInformation(pChar('C:\'), Buffer, 256, @SerialNum, A, B, C, 256) then
Result := inttostr(SerialNum * Cardinal(-1))
else Result := '';
end;
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