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From WiX Wiki at MindCapers

The condition (?) doesn't work in silent mode. To make it work I needed these elements:

   <CustomAction Id="NewerVersion" Error="A later version of [ProductName] is already installed." />

   <InstallExecuteSequence>

     <Custom Action="NewerVersion" After="FindRelatedProducts">NEWERVERSIONDETECTED</Custom>

   </InstallExecuteSequence>