Change windows default printer ... Urgent

Hi People!

I'm trying to change the windows default printer using this code:

http://www.dotnet247.com/247reference/msgs/3/19179.aspx

but when I execute this code, the error: Method not existis or not
implemented.

ocorred in this line: mo.InvokeMethod("SetDefaultPrinter", inParams, null);

mo: ManagementObject


Does anyone know how can I solve that?

tnks a lot

Marcus VinÃ*cius M. Montezano
..Net Developer