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Changes in the Product.wxs:
2 Change the <?define ProductVersionReleaseVersion="1.0.1.xxx" ?> element and <ProductName> in the Product.wxs
3 Change the GUID for the UpgradeCode in the <Product> element.
4 Use the same GUID as in 3 for the <Upgrade> elementID
5 Change the GUID of the ProgramMenuDir" component.Like this <Component Id="ProgramMenuDir" Guid="CHANGE-THIS-GUID">
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